Chapter 2

Literature Review and Technical Reading

The primary goal of literature review is to know the use of content/ideas/approaches

in the literature to correctly identify the problem that is vaguely known beforehand,
to advocate a specific approach adopted to understanding the problem, and to access
the choice of methods used. It also helps the researcher understand clearly that the
research to be undertaken would contribute something new and innovative. The qual-
ity of such review can be determined by evaluating if it includes appropriate breadth
and depth of the area under study, clarity, rigor, consistency, effective analysis.

2.1 New and Existing Knowledge

New knowledge in research can only be interpreted within the context of what is
already known, and cannot exist without the foundation of existing knowledge. In
this chapter, we are going to look at how that foundation of knowledge needs to
be constructed so that our new knowledge is supported by it. The new knowledge
can have vastly different interpretations depending on what the researcher’s back-
ground, and one’s perception of that new knowledge can change from indifference
to excitement (or vice versa), depending on what else one knows. The significance
can normally be argued from the point of view that there is indeed an existing prob-
lem and that it is known by looking at what already exists in the field. The existing
knowledge is needed to make the case that there is a problem and that it is important.
One can infer that the knowledge that is sought to be produced does not yet exist
by describing what other knowledge already exists and by pointing out that this part
is missing so that what we have is original. To do this, one again needs the existing
knowledge: the context, the significance, the originality, and the tools. Where does
this existing knowledge come from? Normally, one finds this knowledge by reading
and surveying the literature in the field that was established long ago and also about

© Springer Nature Singapore Pte Ltd. 2019 9

D. Deb et al., Engineering Research Methodology, Intelligent Systems
Reference Library 153, https://doi.org/10.1007/978-981-13-2947-0_2
10 2 Literature Review and Technical Reading

the more recent knowledge which is in fact always changing. With this foundation in
place, the new knowledge that one will make will be much more difficult to challenge
than without that strong foundation in place which is ensured with lots of references
to the literature.
Often, but not always, the textbooks contain the older established knowledge and
the research papers the newer work. Reading the textbooks on one’s topic provide the
established knowledge and the background to be able to read the newer work usually
recorded in the research papers. Very often, reading a textbook is not too difficult for
it is written as a teaching instrument, and the author of the textbook normally starts
from the basics and take the reader, through everything that one needs to be able to
understand that topic. This is not at all the case with a research paper where the goal
is normally to present a small piece of new knowledge, and that new knowledge will
not have stood the test of time in the same way as the knowledge in a textbook would
have. The research paper is written for other researchers out on the edge of knowledge
and it assumes that the reader already knows a lot in that field. A researcher may find
oneself continually going back to other sources to try and interpret what is going on
in a particular research paper. It can be difficult to find the right work to read, but the
objective with all this reading and learning is to be able to get the knowledge that
one needs to build the foundation.
The review process must explain how a research item builds on another one
[1]. This is because useful research should elucidate how and why certain technical
development took place, so that it is easy for the reader to comprehend why the present
talk is being undertaken, and a good literature survey would provide a convincing
under to that question. An effective review of literature ensures a firm foundation for
advancing knowledge, facilitates theoretical growth, eliminates as areas that might
be of interest, and opens new avenues of possible work. An efficient literature review
is centered around concepts and not authors [2].
Generally, a good literature survey is the first expectation of a supervisor from
the research student, and when done well can create a good impression that the state
of art in the chosen field is well understood. Simple rules for writing an effective
literature review are important for a research scholar, are provided [3, 4]. A good
literature review would not draw hasty conclusions and look into the individual
references to determine the underlying causes/assumptions/mechanisms in each of
them so as to synthesize the available information in a much more meaningful way.
A literature review should be able to summarize as to what is already known from
the state of the art, detail the key concepts and the main factors or parameters and
the underlying relationships between those, describe any complementary existing
approaches, enumerate the inconsistencies or shortcomings in the published work,
identify the reported results that are inconclusive or contradictory, and provide a
compulsive reason to do further work in the field.
A good literature survey is typically a two-step process as enumerated below:
(i) Identify the major topics or subtopics or concepts relevant to the subject under
consideration.
2.1 New and Existing Knowledge 11

(ii) Place the citation of the relevant source (article/patent/website/data, etc.) in

the correct category of the concept/topic/subtopic (with the help of a , for
example).
It could be that as one is reading and comes across something that one considers to
be very important for one’s work, a core principle or a description of something that
just sounds really good, and one is excited to have found it. Naturally, one highlights
that section or underlines it, or put an asterisk in the margin, so that one could come
back to it later. Effectively, one is saying that it is important and hence the marking
so as not to forget it.
After having marked or highlighted the section, it is suggested that the paper
be put away or the book be closed. Then one should write about the highlighted
part without copying it. As one writes about why one thinks that part is important
and what it contains, one is automatically changing it and making it fit into one’s
foundation in the way that makes sense. There are shaping and crafting of that piece
of knowledge to fit where one needs it to be. To build the knowledge foundation, one
needs to be reading and learning continually. But that is not enough, one also needs
to be writing about what one has read.
A comprehensive literature survey should methodically analyze and synthesize
quality archived work, provide a firm foundation to a topic of interest and the choice
of suitable research methodologies, and demonstrate that the proposed work would
make a novel contribution to the overall field of research.

2.2 Analysis and Synthesis of Prior Art

After collecting the sources, usually articles, intended to be used in the literature
review, the researcher is ready to break down each article and identify the useful
content in it, and then synthesize the collection of articles (integrate them and identify
the conclusions that can be made from the articles as a group) [5]. A literature survey
grid of N topics and M sources is shown below to help crystallize the information
in different categories.
A researcher should analyze the relevant information ascertained in Table 2.1 by
undertaking the following steps:
(i) Understanding the hypothesis,
(ii) Understanding the models and the experimental conditions used,
(iii) Making connections,
(iv) Comparing and contrasting the various information, and
(v) Finding out the strong points and the loopholes.
It is always good to be suspicious of the claims made in the sources that have
been thoroughly reviewed, especially in the case of tall claims. If one is amenable
to easily accept whatever is available in the literature, one may find it difficult to go
12 2 Literature Review and Technical Reading

Table 2.1 The literature Source 1 Source 2 … Source M

survey grid
Topic 1 
Topic 2  
..
.

..
.

Topic N  

beyond it in one’s own work and may also fail to carefully analyze with a suspicious
bent of mind one’s own results subsequently.
The goal of literature survey is to bring out something new to work on through
the identification of unsolved issues, determine the problems in the existing models
or experimental designs, and present a novel idea and recommendations.
No matter where one gets the available information, one needs to critically evaluate
each resource that the researcher wishes to cite. This methodology analyzes available
materials to determine suitability for the intended research. Relying on refereed
articles published in scholarly journals or granted patents can save the researcher a
lot of time. Here are a few criteria that could help the researcher in the evaluation of
the information under study:
• Authority: What are the author’s credentials and affiliation? Who publishes the
information?
• Accuracy: Based on what one already knows about the topic or from reading other
sources, does the information seem credible? Does the author cite other sources
in a reference list or bibliography, to support the information presented?
• Scope: Is the source at an appropriate comprehension or research level?
There are other criteria to consider as well, such as currency, objectivity, and
purpose. It is important to ensure that the search question is neither too narrow nor
too broad.

2.3 Bibliographic Databases

“Bibliographic databases” refer to “abstracting and indexing services” useful for

collecting citation-related information and possibly abstracts of research articles
from scholarly literature and making them available through search. Performing
simultaneous searches through such large databases may allow researchers to overtly
rely on any one database and be limited by the intrinsic shortcoming of any one of
them for quality research [6]. A researcher should be able to quickly identify the
2.3 Bibliographic Databases 13

databases that are of use in the idea or problem that one wishes to explore. In this
section, we present some details about a few of the popular bibliographic databases
most sought after by engineering researchers, but do not attempt to provide exhaustive
details.

2.3.1 Web of Science

Web of Science (formerly known as ISI or Thomson Reuters) includes multiple

databases, as well as specialized tools. It is a good search tool for scholarly materials
requiring institutional license and allows the researcher to search in a particular topic
of interest, which can be made by selection in fields that are available in drop down
menu such as title, topic, author, address, etc. The tool also allows sorting by number
of citations (highest to lowest), publication date.1
Put quotes around phrases, add more keywords, or use the “Refine Results” panel
on the left to narrow down the search by keyword, phrases in quotation marks, type of
material such as peer-reviewed journal articles, date, language, and more. Expanding
the search results is possible by looking for alternate word endings, breaking the
search concepts down, thinking of alternate search terms (including scientific names
if applicable) and connecting them with OR, and using the database’s features for
finding additional references. “Cited reference search” option enables a researcher
to trace articles which have cited a formerly published paper. Using this element,
it is possible to find how a familiar idea has been applied, improved, or extended
subsequently.
A structured search like this that enables narrowing and refining what one is
looking for is effective to ensure that the results throw up relevant sources and time
spent in studying those is likely to be well utilized. Based on the researcher’s need the
search result can be broadened or narrowed down using the built-in fields provided
in this website. When clicked on any of the search results, this website provides the
title of the paper, authors, the type of journal, volume, issue number and year of
publication, abstract, keywords, etc., so that the researcher has enough information
to decide if it is worthwhile to acquire the full version of the paper.

2.3.2 Google and Google Scholar

Google is a great place to start one’s search when one is starting out on a topic. It can
be helpful in finding freely available information, such as reports from governments,
organizations, companies, and so on. However, there are limitations:

1 https://clarivate.com/products/web-of-science/.
14 2 Literature Review and Technical Reading

(i) It’s a “black box” of information. It searches everything on the Internet, with
no quality control—one does not know where results are coming from.
(ii) There are limited search functionality and refinement options.
What about Google Scholar? Google Scholar limits one’s search to scholarly
literature. However, there are limitations:
1. Some of the results are not actually scholarly. An article may look scholarly at
first glance, but is not a good source upon further inspection.
2. It is not comprehensive. Some publishers do not make their content available to
Google Scholar.
3. There is limited search functionality and refinement options.
There are search operators that can be used to help narrow down the results.
These help one find more relevant and useful sources of information. Operators can
be combined within searches. Here are some basic ones that one can use:
(i) OR—Broadens search by capturing synonyms or variant spellings of a concept.
Example: Synchronous OR asynchronous will find results that have either term
present.
(ii) Brackets/Parentheses ( )—Gather OR’d synonyms of a concept together, while
combining them with another concept. Example: RAM (synchronous OR asyn-
chronous).
(iii) Quotation marks “ ”—Narrow the search by finding words together as a phrase,
instead of separately. Example: RAM (synchronous OR asynchronous) “Texas
Instruments”.
(iv) Site—limits the search to results from a specific domain or website. This oper-
ator is helpful when searching specific websites such as the BC government,
which is Example: RAM (synchronous OR asynchronous) “Texas Instruments”
site: http://ieeexplore.ieee.org.
(v) Filetype—limits the search to results with a specific file extension one could
look for pdf’s, PowerPoint presentations, Excel spreadsheets, and so on. Exam-
ple: RAM (synchronous OR asynchronous) “Texas Instruments” site: http://
ieeexplore.ieee.org, filetype: pdf.
The Search Tools button at the top of the Google results gives you a variety of other
options, such as limiting the results by date. There are other operators and tools that
one can use in Google and Google Scholar. Google is but one search tool a researcher
can use—it is not the only one!
It can be hard to sift through all the results in Google or Google Scholar, especially
if the intent is to find scholarly resources from a specific subject area. To find the best
resources on a topic, one should search in academic databases, in addition to Google.
Databases provide access to journal articles and conference proceedings, as well as
other scholarly resources. One gets more relevant and focused results, because they
have better quality control and search functionality. One should choose a database
based on subject area, date coverage, and publication type. Interfaces vary between
databases, but the search techniques remain essentially the same.
2.4 Effective Search: The Way Forward 15

2.4 Effective Search: The Way Forward

A scholarly publication is one wherein the published outcome is authored by

researchers in a specific field of skill. Such work cites all source contents used and
is generally peer reviewed for accuracy and validity before publication. Essentially,
the audience for such works is fellow experts and students in the field. The content
is typically more complex and advanced than those found in general magazines.
While most of the engineering researchers need to refer articles that appear in
scholarly journals, books or other peer-reviewed sources, there is also a substantially
useful content in more popular publications. These are informal in approach and aim
to reach a large number of readers including both the experts in the filed and also
amateurs, but the content focuses on news and trends in the field. Research outcomes
are not typically first disseminated here but are usually meant for general reading.
A researcher should use all search tools for comprehensive search. No one place
or one source exists that will provide all the information one needs; one will likely
need to look in all the places that would be described in this chapter and in others
not mentioned.
A researcher must consider what type of information is needed, and where it could
be found. Not all information is available online. Some information is only available
in print. It can take time for scholarly and peer-reviewed information to be published.
One might not be able to find scholarly information about something currently being
reported in the news. The information may not be available, or studies on a topic
of interest to the researcher have not occurred. In such a case, the researcher should
look for similar studies that would be applicable to the specific topic; look for broad
information (general process, technology, etc.), as well as information that addresses
the specific context of the researcher’s report.
Searching is an iterative process:
• Experiment with different keywords and operators;
• Evaluate and assess results, use filters;
• Modify the search as needed; and
• When relevant articles are found, look at their citations and references.
After the search is complete, the researcher needs to engage in critical and thor-
ough reading, making observation of the salient points in those sources, and summa-
rize the findings. A detailed comparison and contrast of the findings is also required
to be done. This entire process may be needed to be done multiple times. The con-
clusion of the entire process of literature survey includes a summary of the relevant
and important work done, and also the identification of the missing links and the
challenges in the open problems in the area under study. One must note that the
literature survey is a continuous and cyclical process that may involve the researcher
going back and forth till the end of the research project.
Not many people begin research work in their graduate program with an already
acquired skill to efficiently parse math-heavy articles quickly, but those who eventu-
ally succeed in an engineering research career quickly develop that skill from reading
16 2 Literature Review and Technical Reading

a lot of papers, seeking help in understanding confusing parts, and getting through
relevant coursework to build up the required skills and intuition.
It is very important to not lose sight of the purpose of an extensive search or
literature survey, for it is possible to spend a very significant amount of one’s time
doing so and actually falsely think that one is working hard. Nothing will come of it
unless one is an active reader and spends sufficient time to develop one’s own ideas
build on what one has read. It is not as if literature survey ends and then research
begins, for new literature keeps appearing, and as one’s understanding of the problem
grows, one finds new connections and related/evolving problems which may need
more search. It is mandatory for a Ph.D. scholar to write a synopsis of the topic
and submit it to the doctoral committee for approval. During this stage, the scholar
needs to undertake an extensive literature survey connected with the problem. For
this purpose, the archived journals and published or unpublished bibliographies are
the first place to check out. One source leads to another.

2.5 Introduction to Technical Reading

It is now imperative for any active researcher to keep oneself abreast with research
outcomes in their field of interest. Finding the right work to read can be difficult.
The literature where knowledge is archived is very fragmented and there are bits
and pieces all over the place. Very rarely will one find everything that one wants
close together in one place. However, it is obvious that the number of papers relevant
to a particular researcher is very few, compared to the actual number of research
papers available from peer-reviewed technical sources. It is also important to know
where to read from; relying on refereed journals and books published by reputed
publishers is always better than relying on easily available random articles off the
web. While reading an engineering research paper, the goal is to understand the
technical contributions that the authors are making.
Given the abundance of journal articles, it is useful to adopt a quick, purposeful,
and useful way of reading these manuscripts [7]. It is not the same as reading a
newspaper. It may require rereading the paper multiple times and one might expect
to spend many hours reading the paper. A simple, efficient, and logical approach
is described in this section for identifying articles and reading them suitably for
effective research.
Amount of time to be spent will get ascertained after an initial skimming through
the paper to decide whether it is worth careful reading. There will also be papers
where it is not worth reading all the details in the first instance. It is quite possible that
the details are of limited value, or simply one does not feel competent to understand
the information yet.
Start out the skimming process by reading the title and keywords (these are any-
ways, probably what caught the initial attention in the first place). If on reading these,
it does not sufficiently seem to be interesting; it is better to stop reading and look for
2.5 Introduction to Technical Reading 17

something else to read. One should then read the abstract to get an overview of the
paper in minimum time. Again, if it does not seem sufficiently important to the field
of study, one should stop reading further. If the abstract is of interest, one should skip
most of the paper and go straight to the conclusions to find if the paper is relevant
to the intended purpose, and if so, then one should read the figures, tables, and the
captions therein, because these would not take much time but would provide a broad
enough idea as to what was done in the paper.
If the paper has continued to be of interest so far, then one is now ready to delve
into the Introduction section to know the background information about the work and
also to ascertain why the authors did that particular study and in what ways the paper
furthers the state of the art. The next sections to read are the Results and Discussion
sections which is really the heart of the paper. One should really read further sections
like the Experimental Setup/Modeling, etc., only if one is really interested and wishes
to understand exactly what was done to better understand the meaning of the data
and its interpretation.
As one works through the literature in this way, one should consider not only the
knowledge that is written down but also the reputation of the people who made that
knowledge. A researcher will always need to be searching for the relevant literature
and keeping up to date with it. If one is busy with a small project, the advisor might
just give a single important paper to read. But with a larger one, you will be searching
for one’s own literature to read. For this one will need a strategy as there is just too
much work out there to read everything.

2.6 Conceptualizing Research

The characteristics of a research objective are that it must have new knowledge at
the center, and that it must be accepted by the community of other researchers and
recognized as significant. But how do we actually conceptualize the research? Besides
being original and significant, a good research problem should also be solvable or
achievable. This requirement already asks us to think about the method and the tools
that could be used to obtain that new knowledge. Now, the significance and the
originality and all the theory that we read and tools and methods that we need to take
on a problem, all of these normally come from the existing recorded literature and
knowledge in the field.
Coming up with a good research objective, conceptualizing the research that meets
all of these requirements is a tough thing to do. It means that one must already be
aware of what is in the literature. That is, by the time one actually has a good research
objective, one is probably already an expert at the edge of knowledge else it is difficult
to say with confidence that one has a good research objective. If one is doing research
at the Ph.D. level or higher, then conceptualizing the research is probably something
that one needs to do oneself. This is a very tough step because one needs to know all
that literature in the field.
18 2 Literature Review and Technical Reading

So, when working at the Ph.D. level, one needs to be prepared to become that
expert, one needs to be continually reading the literature so as to bring together the
three parts: (i) significant problem, (ii) the knowledge that will address it, and (iii)
a possible way to make that new knowledge. How these three aspects would come
together will be different for every person doing research and it will be different in
every field, but the only way to be that expert is by immersing oneself in the literature
and knowing about what already exists in the field.
However, if one is working on a research project that is of a smaller scope than a
Ph.D., let us say a master’s thesis, then conceptualizing the research is possibly too
tough to do, and one does not have the time that it takes to become that expert at
the edge of knowledge. In this case, the researcher needs the help of someone else,
typically the supervisor who may already be an expert and an active researcher in that
field, and may advise on what a good research objective might be. An established
researcher in any field should be able to immediately point to the landmark literature
that one should read first. Otherwise one would need to spend a lot of time reading
the literature to discover.
As engineers, we like to build things, and that’s good, but the objective of research
is to make knowledge. If one’s research is about building something, one ought to
take a step back and ask if new knowledge is being formulated. Even if what one is
building is new and has never been built before, if it is something that any experienced
and competent engineer could have come up with, one runs the risk of one’s work
being labeled obvious and rejected as research.

2.7 Critical and Creative Reading

Reading a research paper is a critical process. The reader should not be under the
assumption that reported results or arguments are correct. Rather, being suspicious
and asking appropriate questions is in fact a good thing. Have the authors attempted
to solve the right problem? Are there simpler solutions that have not been considered?
What are the limitations (both stated and ignored) of the solution and are there any
missing links? Are the assumptions that were made reasonable? Is there a logical
flow to the paper or is there a flaw in the reasoning? These need to be ascertained
apart from the relevance and the importance of the work, by careful reading.
Use of judgemental approach and boldness to make judgments is needed while
reading. Flexibility to discard previous erroneous judgments is also critical. Addi-
tionally, it is important to ascertain whether the data presented in the paper is right
data to substantiate the argument that was made in the paper and whether the data
was gathered and interpreted in a correct manner. It is also important to decipher
whether some other dataset would have been more compelling.
Critical reading is relatively easy. It is relatively easier to critically read to find
the mistakes than to read it so as to find the good ideas in the paper. Anyone who has
been a regular reviewer of journal articles would agree to such a statement. Reading
2.7 Critical and Creative Reading 19

creatively is harder, and requires a positive approach in search. In creative reading, the
idea is to actively look for other applications, interesting generalizations, or extended
work which the authors might have missed? Are there plausible modifications that
may throw up important practical challenges? One might be able to decipher properly
if one would like to start researching an extended part of this work, and what should
be the immediate next aspect to focus upon.

2.8 Taking Notes While Reading

A researcher reads to write and writes well only if the reading skills are good. The
bridge between reading and actually writing a paper is the act of taking notes during
and shortly after the process of reading. There is a well-known saying that the faintest
writing is better than the best memory, and it applies to researchers who need to read
and build on that knowledge to write building on the notes taken. Many researchers
take notes on the margins of their copies of papers or even digitally on an article
aggregator tool. In each research paper, there are a lot of things that one might like
to highlight for later use such as definitions, explanations, and concepts. If there are
questions of criticisms, these need to be written down so as to avoid being forgotten
later on. Such efforts pay significantly when one has to go back and reread the same
content after a long time.
On completing a thorough reading, a good technical reading should end with a
summary of the paper in a few sentences describing the contributions. But to elucidate
the technical merit, the paper needs to be looked at from comparative perspective
with respect to existing works in that specific area. A thorough reading should bring
out whether there are new ideas in the paper, or if existing ideas were implemented
through experiments or in a new application, or if different existing ideas were
brought together under a novel framework. Obviously, the type of contribution a
paper is actually making can be determined better by having read other papers in the
area.

2.9 Reading Mathematics and Algorithms

Mathematics is often the foundation of new advances, for evolution and development
of engineering research and practice. An engineering researcher generally cannot
avoid mathematical derivations or proofs as part of research work. In fact, these are
the heart of any technical paper. Therefore, one should avoid skimming them. By
meticulous reading of the proofs or algorithms, after having identified the relevance
of the paper, one can develop sound understanding about the problem that the authors
have attempted to solve.
20 2 Literature Review and Technical Reading

Nonetheless, one might skim a technical section if it seems like an explanation

of something already known, or if it is too advanced for the research at the present
moment and needs additional reading to be understandable, or if it seems to special-
ized and unlikely to be needed in the course of the research program in which case
one can get back to it later on. Implementation of an intricate algorithm in program-
ming languages such as C, C++ or Java is prone to errors. And even if the researcher
is confident about the paper in hand, and thinks that the algorithm will work, there is
a fair chance that it will not work at all. So one may wish to code it quickly to check
if it actually works.

2.10 Reading a Datasheet

Researchers in different fields of engineering will need to read certain types of doc-
uments. For example, mechanical and civil engineers would need to read drawings
related to mechanical parts and buildings. Researchers in the field of electronics
need to read datasheets. On occasions, researchers in other fields may also need to
incorporate a certain electronic part in which case careful reading of the datasheet is
imperative. The same principles like initial skimming of the datasheet are required
to ascertain whether further careful reading is needed.
Datasheets are instruction manuals for electronic components, which (hopefully)
details what a component does and how one may use it. Datasheets enable a researcher
(or a working professional) to design a circuit or debug any given circuit with that
component. The first page of the datasheet usually summarizes a part’s function and
features, basic specifications, and usually provides a functional block diagram with
the internal functions of the part.
A pinout provides the physical location of a part’s pins, with special mark for pin
1 so that the part can be correctly plugged into the circuit. Some parts also provide
graphs showing performance versus various criteria (supply voltage, temperature,
etc.), and safe region for reliable operation which should be carefully read and noted
by the researcher. One should be also in the lookout for truth tables which describe
what sort of inputs provide what types of outputs, and also timing diagrams which
lay out how and at what speed data is sent and received from the part. Datasheets
usually end with accurate dimensions of the packages a part is available in. This is
useful for printed circuit board (PCB) layout.
When working with a new part, or when deciding which part to use in the research
work, it is recommended to carefully read that part’s datasheet to come up with a bit
of shortcut that may potentially save many hours later on.
As already stated, an engineering researcher will have documents to read which
are specific to the branch of engineering in which one is researching in. However,
the objective of the authors herein has been to use datasheets as an example to state
the need to pay attention to the art of reading such documents. Technical published
papers or books are not the only contents that a researcher has to master reading!
References 21

References

1. Shaw, J. (1995). System, 23(3), 325–334.

2. Webster, J., & Watson, R. T. (2002). MIS Quarterly, 26(2), 13–23.
3. Pautasso, M. (2013). Ten simple rules for writing a literature review. Plos Computational Biology,
9(7), e1003149.
4. Maier, H. (2013). What constitutes a good literature review and why does its quality matter?
Environmental Modelling & Software, 43, 3–4.
5. Galvan, J. (2006). Writing literature reviews (3rd ed.). Glendale, CA: Pyrczak Publishing.
6. Gasparyan, A. (2013). Bibliographic databases: Some critical points. Journal of Korean Medical
Science, 28(6), 799.
7. Subramanyam, R. (2013). Art of reading a journal article: Methodically and effectively. Journal
of Oral and Maxillofacial Pathology, 17(1), 65.