Editing CAPTCHA (section)

== References ==
{{Reflist|30em|refs=
<ref name="abhl">{{cite conference
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| first1 = Luis
| last2 = Blum
| first2 = Manuel
| last3 = Hopper
| first3 = Nicholas J.
| last4 = Langford
| first4 = John
| title = Advances in Cryptology—EUROCRYPT 2003
| date = May 2003
| chapter = CAPTCHA: Using Hard AI Problems for Security
| series = Lecture Notes in Computer Science
| volume = 2656
| pages = 294–311
| conference = EUROCRYPT 2003: International Conference on the Theory and Applications of Cryptographic Techniques
| chapter-url = https://link.springer.com/content/pdf/10.1007/3-540-39200-9_18.pdf
| doi = 10.1007/3-540-39200-9_18
| isbn = 978-3-540-14039-9
| doi-access = free
| access-date = 30 August 2019
| archive-date = 4 May 2019
| archive-url = https://web.archive.org/web/20190504115630/https://link.springer.com/content/pdf/10.1007%2F3-540-39200-9_18.pdf
| url-status = live
}}</ref>
<ref name="bursz2">{{cite conference
| last1 = Bursztein
| first1 = Elie
| last2 = Aigrain
| first2 = Johnathan
| last3 = Mosciki
| first3 = Angelika
| last4 = Michell
| first4 = John C.
| date = August 2014
| title = The End is Nigh: Generic Solving of Text-based CAPTCHAs
| conference = WoOT 2014: Usenix Workshop on Offensive Security
| url = https://www.elie.net/publication/the-end-is-nigh-generic-solving-of-text-based-captchas
| access-date = 5 April 2016
| archive-date = 16 April 2016
| archive-url = https://web.archive.org/web/20160416212924/https://www.elie.net/publication/the-end-is-nigh-generic-solving-of-text-based-captchas
| url-status = live
}}</ref>
<ref name="motoyama">{{cite conference
| last1 = Motoyama
| first1 = Marti
| last2 = Levchenko
| first2 = Kirill
| last3 = Kanich
| first3 = Chris
| last4 = McCoy
| first4 = Damon
| last5 = Geoffrey
| first5 = Voelker
| last6 = Savage
| first6 = Stefan
| date = August 2010
| title = Re: CAPTCHAs-Understanding CAPTCHA-Solving Services in an Economic Context.s
| conference = USENIX Security Symposium, 2010
| url = http://static.usenix.org/event/sec10/tech/full_papers/Motoyama.pdf
| access-date = 5 April 2016
| archive-date = 29 May 2016
| archive-url = https://web.archive.org/web/20160529023244/http://static.usenix.org/event/sec10/tech/full_papers/Motoyama.pdf
| url-status = live
}}</ref>
}}