APA (7th ed.) Citation

ATHANASOPOULOS, E., & ANTONATOS, S. (2006). Enhanced CAPTCHAs: Using animation to tell humans and computers apart. Lecture notes in computer science, 97-108.

Chicago Style (17th ed.) Citation

ATHANASOPOULOS, Elias, and Spiros ANTONATOS. "Enhanced CAPTCHAs: Using Animation to Tell Humans and Computers Apart." Lecture Notes in Computer Science 2006: 97-108.

MLA (9th ed.) Citation

ATHANASOPOULOS, Elias, and Spiros ANTONATOS. "Enhanced CAPTCHAs: Using Animation to Tell Humans and Computers Apart." Lecture Notes in Computer Science, 2006, pp. 97-108.

Warning: These citations may not always be 100% accurate.