research-article

Disambiguation of imprecise input with one-dimensional rotational text entry

Authors:

William S. Walmsley,

W. Xavier Snelgrove,

Khai N. TruongAuthors Info & Claims

ACM Transactions on Computer-Human Interaction (TOCHI), Volume 21, Issue 1

Article No.: 4, Pages 1 - 40

https://doi.org/10.1145/2542544

Published: 01 February 2014 Publication History

Abstract

We introduce a distinction between disambiguation supporting continuous versus discrete ambiguous text entry. With continuous ambiguous text entry methods, letter selections are treated as ambiguous due to expected imprecision rather than due to discretized letter groupings. We investigate the simple case of a one-dimensional character layout to demonstrate the potential of techniques designed for imprecise entry. Our rotation-based sight-free technique, Rotext, maps device orientation to a layout optimized for disambiguation, motor efficiency, and learnability. We also present an audio feedback system for efficient selection of disambiguated word candidates and explore the role that time spent acknowledging word-level feedback plays in text entry performance. Through a user study, we show that despite missing on average by 2.46--2.92 character positions, with the aid of a maximum a posteriori (MAP) disambiguation algorithm, users can average a sight-free entry speed of 12.6wpm with 98.9% accuracy within 13 sessions (4.3 hours). In a second study, expert users are found to reach 21wpm with 99.6% accuracy after session 20 (6.7 hours) and continue to grow in performance, with individual phrases entered at up to 37wpm. A final study revisits the learnability of the optimized layout. Our modeling of ultimate performance indicates maximum overall sight-free entry speeds of 29.0wpm with audio feedback, or 40.7wpm if an expert user could operate without relying on audio feedback.

References

[1]

Apple. 2011. Apple iPhone. Retrieved from http://www.apple.com/iphone/.

[2]

J. Arnott and M. Javed. 1992. Probabilistic character disambiguation for reduced keyboards using small text samples. Augmentative and Alternative Communication 8, 3 (1992), 215--223.

[3]

S. Azenkot, J. O. Wobbrock, S. Prasain, and R. E. Ladner. 2012. Input finger detection for nonvisual touch screen text entry in Perkinput. In Proceedings of the 2012 Graphics Interace Conference (GI’12). Canadian Information Processing Society, Toronto, Ontario, Canada, 121--129.

Digital Library

[4]

L. R. Bahl, F. Jelinek, and R. L. Mercer. 1983. A maximum likelihood approach to continuous speech recognition. IEEE Tran. Pattern Analysis and Machine Intelligence 5, 2 (March 1983), 179--190. http://dx.doi.org/10.1109/TPAMI.1983.4767370

Digital Library

[5]

X. Bi, C. Chelba, T. Ouyang, K. Partridge, and S. Zhai. 2012. Bimanual gesture keyboard. In Proceedings of the 25th Annual ACM Symposium on User Interface Software and Technology (UIST’12). ACM, New York, 137--146. http://dx.doi.org/10.1145/2380116.2380136

Digital Library

[6]

M. Bonner, J. Brudvik, G. Abowd, and W. Edwards. 2010. No-look notes: Accessible eyes-free multi-touch text entry. In Proceedings of the 8th International Conference on Pervasive Computing (Pervasive’10). Springer-Verlag, Berlin, 409--426. http://dx.doi.org/10.1007/978-3-642-12654-3_24

Digital Library

[7]

R. Borland. 1995. Running Microsoft Word for Windows 95. Microsoft Press.

Digital Library

[8]

J. Clawson, K. Lyons, T. Starner, and E. Clarkson. 2005. The impacts of limited visual feedback on mobile text entry for the Twiddler and mini-QWERTY keyboards. In Proceedings of the 9th IEEE International Symposium on Wearable Computers (ISWC’05). IEEE Computer Society, Washington, DC, 170--177. http://dx.doi.org/10.1109/ISWC.2005.49

Digital Library

[9]

A. Cox, P. Cairns, A. Walton, and S. Lee. 2008. Tlk or txt&quest; Using voice input for SMS composition. Pers. Ubiquitous Comput. 12, 8 (2008), 567--588. http://dx.doi.org/10.1007/s00779-007-0178-8

Digital Library

[10]

M. Davies. 2008. The Corpus of Contemporary American English (COCA): 400+ million words, 1990-present. Retrieved from http://www.americancorpus.org.

[11]

E. Desautels and S. B. Soffer. 1974. Touch-tone input techniques: Data entry using a constrained keyboard. In Proceedings of the 1974 Annual Conference-Volume 1. ACM, 245--253.

Digital Library

[12]

M. Dunlop and J. Levine. 2012. Multidimensional Pareto optimization of touchscreen keyboards for speed, familiarity and improved spell checking. In Proceedings of the 2012 ACM Annual Conference on Human Factors in Computing Systems (CHI’12). ACM, New York, 2669--2678. http://doi.acm.org/10.1145/2207676.2208659

Digital Library

[13]

A. Dvorak and W. L. Dealey. 1936. Typewriter Keyboard. U.S. Patent No. 2040248.

[14]

Arthur D. Fisk, William L. Derrick, and Walter Schneider. 1983. The assessment of workload: Dual task methodology. Proceedings of the Human Factors and Ergonomics Society Annual Meeting. 27, 3 (1983), 229--233. http://pro.sagepub.com/content/27/3/229.abstract

[15]

P. M. Fitts. 1954. The information capacity of the human motor system in controlling the amplitude of movement. J. Exp. Psychol. 47, 6 (1954), 381--391.

[16]

É. Grandjean. 1980. Fitting the Task to the Man: An Ergonomic Approach. Taylor & Francis, London.

[17]

N. Green, J. Kruger, C. Faldu, and R. St. Amant. 2004. A reduced QWERTY keyboard for mobile text entry. In Extended Abstracts of the SIGCHI Conference on Human Factors in Computing Systems (CHI EA’04). 1429--1432.

Digital Library

[18]

S. G. Hart and L. E. Staveland. 1988. Development of NASA-TLX (task load index): Results of empirical and theoretical research. In Human Mental Workload, P. A. Hancock and N. Meshkati (Eds.). Elsevier, 239--250.

[19]

J. B. Israel, G. L. Chesney, C. D. Wickens, and E. Donchin. 1980. P300 and tracking difficulty: Evidence for multiple resources in dual-task performance. Psychophysiology 17 (1980), 259--273.

[20]

M. Jain and R. Balakrishnan. 2012. User learning and performance with bezel menus. In Proceedings of the 2012 ACM Annual Conference on Human Factors in Computing Systems (CHI’12). ACM, New York, 2221--2230.

Digital Library

[21]

E. Jones, J. Alexander, A. Andreou, P. Irani, and S. Subramanian. 2010. GesText: Accelerometer-based gestural text-entry systems. In Proceedings of the 28th International Conference on Human Factors in Computing Systems (CHI’10). ACM, New York, 2173--2182. http://doi.acm.org/10.1145/1753326.1753655

Digital Library

[22]

A. K. Karlson, B. B. Bederson, and J. L. Contreras-Vidal. 2008. Understanding one-handed use of mobile devices. In Handbook of Research on User Interface Design and Evaluation for Mobile Technology, J. Lumsden (Ed.). Information Science Reference, Chapter VI, 86--101.

[23]

P.-O. Kristensson and S. Zhai. 2004. SHARK²: A large vocabulary shorthand writing system for pen-based computers. In Proceedings of the 17th Annual ACM Symposium on User Interface Software and Technology (UIST’04). ACM, New York, 43--52. http://dx.doi.org/10.1145/1029632.1029640

Digital Library

[24]

C. Kushler. 1998. AAC using a reduced keyboard. In Technology and Persons with Disabilities. Center on Disabilities, California State University. Retrieved from http://www.csun.edu/cod/conf/1998/proceedings/csun98_140.htm.

[25]

G. W. Lesher, B. J. Moulton, and D. J. Higginbotham. 1998. Optimal character arrangements for ambiguous keyboards. IEEE Trans. Rehabil. Eng. 6, 4 (Dec. 1998), 415--423.

[26]

F. C. Y. Li, R. Guy, K. Yatani, and K. N. Truong. 2011. The 1Line keyboard: A QWERTY layout in a single line. In Proceedings of the 24th Annual ACM Symposium on User Interface Software and Technology (UIST’11). ACM, New York, 461--470.

Digital Library

[27]

K. Lyons, D. Plaisted, and T. Starner. 2004a. Expert chording text entry on the Twiddler one-handed keyboard. In Proceedings of the 8th International Symposium on Wearable Computers (ISWC’04). IEEE Computer Society, Washington, DC, 94--101.

Digital Library

[28]

K. Lyons, T. Starner, D. Plaisted, J. Fusia, A. Lyons, A. Drew, and E. W. Looney. 2004b. Twiddler typing: one-handed chording text entry for mobile phones. In Proceedings of the SIGCHI conference on Human Factors in Computing Systems (CHI’04). ACM, New York, 671--678. http://doi.acm.org/10.1145/985692.985777

Digital Library

[29]

I. S. MacKenzie and K. Tanaka-Ishii. 2007. Text entry using a small number of buttons. Text Entry Systems: Mobility, Accessibility, Universality. Morgan Kaufmann, 105--121.

[30]

I. S. MacKenzie. 1992. Fitts’ law as a research and design tool in human-computer interaction. Hum.-Comput. Interact. 7, 1 (March 1992), 91--139. http://dx.doi.org/10.1207/s15327051hci0701_3

Digital Library

[31]

I. S. MacKenzie. 2002. A note on calculating entry speed. Unpublished work. Available at http://www.yorku.ca/mack/RN-TextEntrySpeed.html.

[32]

I. S. Mackenzie and T. Felzer. 2010. SAK: Scanning ambiguous keyboard for efficient one-key text entry. ACM Trans. Comput.-Hum. Interact. 17, 3 (July 2010), Article 11, 39 pages. http://doi.acm.org/10.1145/1806923.1806925

Digital Library

[33]

I. S. MacKenzie, H. Kober, D. Smith, T. Jones, and E. Skepner. 2001. LetterWise: Prefix-based disambiguation for mobile text input. In Proceedings of the 14th Annual ACM Symposium on User Interface Software and Technology (UIST’01). ACM, New York, 111--120. http://dx.doi.org/10.1145/502348.502365

Digital Library

[34]

I. S. MacKenzie and R. W. Soukoreff. 2002. A character-level error analysis technique for evaluating text entry methods. In Proceedings of the second Nordic conference on Human-computer interaction (NordiCHI’02). ACM, New York, 243--246. http://doi.acm.org/10.1145/572020.572056

Digital Library

[35]

I. S. MacKenzie and R. W. Soukoreff. 2003. Phrase sets for evaluating text entry techniques. In CHI’03 Extended Abstracts on Human Factors in Computing Systems(CHI EA’03). ACM, New York, 754--755. http://doi.acm.org/10.1145/765891.765971

Digital Library

[36]

I. S. MacKenzie and S. X. Zhang. 1999. The design and evaluation of a high-performance soft keyboard. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (CHI’99). ACM, New York, 25--31. http://dx.doi.org/10.1145/302979.302983

Digital Library

[37]

J. Mankoff and G. D. Abowd. 1998. Cirrin: a word-level unistroke keyboard for pen input. In Proceedings of the 11th Annual ACM Symposium on User Interface Software and Technology (UIST’98). ACM, New York, 213--214. http://doi.acm.org/10.1145/288392.288611

Digital Library

[38]

G. A. Miller. 1956. The magical number seven, plus or minus two: some limits on our capacity for processing information. Psychol. Rev. 63, 2 (1956), 81--97.

[39]

J. Oliveira, T. Guerreiro, H. Nicolau, J. Jorge, and D. Gonçalves. 2011. BrailleType: unleashing braille over touch screen mobile phones. In Proceedings of the 13th IFIP TC 13 International Conference on Human-Computer Interaction. Springer-Verlag, Berlin, 100--107.

Digital Library

[40]

K. Partridge, S. Chatterjee, V. Sazawal, G. Borriello, and R. Want. 2002. TiltType: accelerometer-supported text entry for very small devices. In Proceedings of the 15th Annual ACM Symposium on User Interface Software and Technology (UIST’02). ACM, New York, 201--204. http://doi.acm.org/10.1145/571985.572013

Digital Library

[41]

K. Perlin. 1998. Quikwriting: Continuous stylus-based text entry. In Proceedings of the 11th Annual ACM Symposium on User Interface Software and Technology (UIST’98). ACM, New York, 215--216. http://doi.acm.org/10.1145/288392.288613

Digital Library

[42]

M. Rahman, S. Gustafson, P. Irani, and S. Subramanian. 2009. Tilt techniques: Investigating the dexterity of wrist-based input. In Proceedings of the 27th International Conference on Human Factors in Computing Systems (CHI’09). ACM, New York, 1943--1952. http://doi.acm.org/10.1145/1518701.1518997

Digital Library

[43]

M. Silfverberg, I. S. MacKenzie, and P. Korhonen. 2000. Predicting text entry speed on mobile phones. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (CHI’00). ACM, New York, NY, 9--16. http://dx.doi.org/10.1145/332040.332044

Digital Library

[44]

R. W. Soukoreff and I. S. MacKenzie. 2003. Metrics for text entry research: An evaluation of MSD and KSPC, and a new unified error metric. In Proceedings of the SIGCHI conference on Human Factors in Computing Systems (CHI’03). ACM, New York, 113--120. http://doi.acm.org/10.1145/642611.642632

Digital Library

[45]

C. Southern, J. Clawson, B. Frey, G. Abowd, and M. Romero. 2012. An evaluation of BrailleTouch: Mobile touchscreen text entry for the visually impaired. In Proceedings of the 14th International Conference on Human-Computer Interaction with Mobile Devices and Services Companion (MobileHCI’12). ACM, New York, 317--326.

Digital Library

[46]

K. Tanaka-Ishii, Y. Inutsuka, and M. Takeichi. 2002. Entering text with a four-button device. In Proceedings of the 19th International Conference on Computational Linguistics-Volume 1. Association for Computational Linguistics, 1--7.

Digital Library

[47]

H. Tinwala and I. S. MacKenzie. 2009. Eyes-free text entry on a touchscreen phone. In Science and Technology for Humanity (TIC-STH), 2009 IEEE Toronto International Conference. IEEE, New York, 83--88.

[48]

H. Tinwala and I. S. MacKenzie. 2010. Eyes-free text entry with error correction on touchscreen mobile devices. In Proceedings of the 6th Nordic Conference on Human-Computer Interaction: Extending Boundaries (NordiCHI’10). ACM, New York, 511--520. http://doi.acm.org/10.1145/1868914.1868972

Digital Library

[49]

J. Wang, S. Zhai, and J. Canny. 2010. SHRIMP: Solving collision and out of vocabulary problems in mobile predictive input with motion gesture. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (CHI’10). ACM, New York, 15--24. http://dx.doi.org/10.1145/1753326.1753330

Digital Library

[50]

D. Wigdor and R. Balakrishnan. 2003. TiltText: Using tilt for text input to mobile phones. In Proceedings of the 16th Annual ACM Symposium on User Interface Aoftware and Technology (UIST’03). ACM, New York, 81--90. http://doi.acm.org/10.1145/964696.964705

Digital Library

[51]

J. O. Wobbrock and B. A. Myers. 2006. Analyzing the input stream for character-level errors in unconstrained text entry evaluations. ACM Trans. Comput.-Hum. Interact. 13, 4 (December 2006), 458--489. http://doi.acm.org/10.1145/1188816.1188819

Digital Library

[52]

J. O. Wobbrock, B. A. Myers, and J. A. Kembel. 2003. EdgeWrite: A stylus-based text entry method designed for high accuracy and stability of motion. In Proceedings of the 16th Annual ACM Symposium on User Interface Software and Technology (UIST’03). ACM, New York, 61--70. http://doi.acm.org/10.1145/964696.964703

Digital Library

[53]

S. Zhai, M. Hunter, and B. A. Smith. 2000. The metropolis keyboard—an exploration of quantitative techniques for virtual keyboard design. In Proceedings of the 13th Annual ACM Symposium on User Interface Software and Technology (UIST’00). ACM, New York, 119--128. http://doi.acm.org/10.1145/354401.354424

Digital Library

[54]

S. Zhai, M. Hunter, and B. A. Smith. 2002a. Performance optimization of virtual keyboards. Human-Computer Interaction. 89--129.

[55]

S. Zhai and P.-O. Kristensson. 2003. Shorthand writing on stylus keyboard. In Proceedings of the SIGCHI conference on Human Factors in Computing Systems (CHI’03). ACM, New York, 97--104. http://doi.acm.org/10.1145/642611.642630

Digital Library

[56]

S. Zhai and P. O. Kristensson. 2012. The word-gesture keyboard: reimagining keyboard interaction. Commun. ACM 55, 9 (Sept. 2012), 91--101. http://dx.doi.org/10.1145/2330667.2330689

Digital Library

[57]

S. Zhai, A. Sue, and J. Accot. 2002b. Movement model, hits distribution and learning in virtual keyboarding. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (CHI’02). ACM, New York, NY, 17--24. http://dx.doi.org/10.1145/503376.503381

Digital Library

[58]

S. Zhao, P. Dragicevic, M. Chignell, R. Balakrishnan, and P. Baudisch. 2007. Earpod: eyes-free menu selection using touch input and reactive audio feedback. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (CHI’07). ACM, New York, 1395--1404.

Digital Library

Cited By

Yu JNai WSun X(2023)Accurate Raycasting Selection With Rotation Gesture Using a 6-DOF Tracking DeviceIEEE Transactions on Visualization and Computer Graphics10.1109/TVCG.2023.332437330:9(6104-6117)Online publication date: 13-Oct-2023
https://dl.acm.org/doi/10.1109/TVCG.2023.3324373
Shatilov KKwon YLee LChatzopoulos DHui P(2023)MyoKey: Inertial Motion Sensing and Gesture-Based QWERTY Keyboard for Extended RealitiesIEEE Transactions on Mobile Computing10.1109/TMC.2022.315693922:8(4807-4821)Online publication date: 1-Aug-2023
https://doi.org/10.1109/TMC.2022.3156939
Lee LBraud THui P(2023)Embodied Interaction on Constrained Interfaces for Augmented RealitySpringer Handbook of Augmented Reality10.1007/978-3-030-67822-7_10(239-271)Online publication date: 1-Jan-2023
https://doi.org/10.1007/978-3-030-67822-7_10
Show More Cited By

Index Terms

Disambiguation of imprecise input with one-dimensional rotational text entry
1. Human-centered computing
  1. Human computer interaction (HCI)

Recommendations

Evaluation of an ambiguous-keyboard prototype scanning-system with word and character disambiguation
BCS '10: Proceedings of the 24th BCS Interaction Specialist Group Conference

Ambiguous keyboards are common in small-size devices such as mobile phones, but they can be applied to other fields such as Augmentative and Alternative Communications, and specifically addressed to people with severe motor disabilities. This research ...
Designing EdgeWrite Versions for Japanese Text Entry
CW '13: Proceedings of the 2013 International Conference on Cyberworlds

This paper presents our project of designing Edge Write text entry methods for Japanese language. We are developing two versions of Edge Write text entry method for Japanese language: Roman-Kana Edge Write and Katakana Edge Write. Roman-Kana Edge Write ...
Joker key in learning a new text entry method
HCIK '15: Proceedings of HCI Korea

Text entry is a very conservative part of HCI because new text entry techniques often require retraining the users. To minimize the cost of learning we experimented with a joker key. It is a key that can be pressed when the user does not know how to ...

Comments

Please enable JavaScript to view thecomments powered by Disqus.

Information & Contributors

Information

Published In

cover image ACM Transactions on Computer-Human Interaction

ACM Transactions on Computer-Human Interaction Volume 21, Issue 1

February 2014

170 pages

ISSN:1073-0516

EISSN:1557-7325

DOI:10.1145/2582013

Issue’s Table of Contents

Copyright © 2014 ACM.

Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than the author(s) must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected].

Publisher

Association for Computing Machinery

New York, NY, United States

Publication History

Published: 01 February 2014

Accepted: 01 August 2013

Revised: 01 July 2013

Received: 01 June 2012

Published in TOCHI Volume 21, Issue 1

Permissions

Request permissions for this article.

Request Permissions

Check for updates

Author Tags

Qualifiers

Research-article
Research
Refereed

Contributors

Other Metrics

View Article Metrics

Bibliometrics & Citations

Bibliometrics

Article Metrics

15
Total Citations
View Citations
731
Total Downloads

Downloads (Last 12 months)18
Downloads (Last 6 weeks)5

Reflects downloads up to 14 Dec 2024

Other Metrics

View Author Metrics

Citations

Cited By

Yu JNai WSun X(2023)Accurate Raycasting Selection With Rotation Gesture Using a 6-DOF Tracking DeviceIEEE Transactions on Visualization and Computer Graphics10.1109/TVCG.2023.332437330:9(6104-6117)Online publication date: 13-Oct-2023
https://dl.acm.org/doi/10.1109/TVCG.2023.3324373
Shatilov KKwon YLee LChatzopoulos DHui P(2023)MyoKey: Inertial Motion Sensing and Gesture-Based QWERTY Keyboard for Extended RealitiesIEEE Transactions on Mobile Computing10.1109/TMC.2022.315693922:8(4807-4821)Online publication date: 1-Aug-2023
https://doi.org/10.1109/TMC.2022.3156939
Lee LBraud THui P(2023)Embodied Interaction on Constrained Interfaces for Augmented RealitySpringer Handbook of Augmented Reality10.1007/978-3-030-67822-7_10(239-271)Online publication date: 1-Jan-2023
https://doi.org/10.1007/978-3-030-67822-7_10
Youn ELee SKim SShim YChan LLee G(2021)WristDial: An Eyes-Free Integer-Value Input Method by Quantizing the Wrist RotationInternational Journal of Human–Computer Interaction10.1080/10447318.2021.189884837:17(1607-1624)Online publication date: 13-Apr-2021
https://doi.org/10.1080/10447318.2021.1898848
Čejka JChmelík JLiarokapis F(2021)Exploring tilting methods for typing under waterMultimedia Tools and Applications10.1007/s11042-020-09305-780:20(31085-31103)Online publication date: 1-Aug-2021
https://dl.acm.org/doi/10.1007/s11042-020-09305-7
Lee LBraud TLam KYau YHui P(2020)From seen to unseen: Designing keyboard-less interfaces for text entry on the constrained screen real estate of Augmented Reality headsetsPervasive and Mobile Computing10.1016/j.pmcj.2020.10114864(101148)Online publication date: Apr-2020
https://doi.org/10.1016/j.pmcj.2020.101148
Castellucci SMacKenzie IMisra MPandey LArif APaternò FJacucci GRohs MSantoro C(2019)TiltWriterProceedings of the 18th International Conference on Mobile and Ubiquitous Multimedia10.1145/3365610.3365629(1-8)Online publication date: 26-Nov-2019
https://dl.acm.org/doi/10.1145/3365610.3365629
Banovic NSethapakdi THari YDey AMankoff J(2019)The Limits of Expert Text Entry Speed on Mobile Keyboards with AutocorrectProceedings of the 21st International Conference on Human-Computer Interaction with Mobile Devices and Services10.1145/3338286.3340126(1-12)Online publication date: 1-Oct-2019
https://dl.acm.org/doi/10.1145/3338286.3340126
Gupta AJi CYeo HQuigley AVogel DBrewster SFitzpatrick GCox AKostakos V(2019)RotoSwypeProceedings of the 2019 CHI Conference on Human Factors in Computing Systems10.1145/3290605.3300244(1-12)Online publication date: 2-May-2019
https://dl.acm.org/doi/10.1145/3290605.3300244
Lee LYung Lam KYau YBraud THui P(2019)HIBEY: Hide the Keyboard in Augmented Reality2019 IEEE International Conference on Pervasive Computing and Communications (PerCom10.1109/PERCOM.2019.8767420(1-10)Online publication date: Mar-2019
https://doi.org/10.1109/PERCOM.2019.8767420
Show More Cited By

View Options

Login options

Check if you have access through your login credentials or your institution to get full access on this article.

Full Access

Get this Article

View options

PDF

View or Download as a PDF file.

eReader

View online with eReader.

Media

Figures

Other

Tables

View Issue’s Table of Contents