Gerardo Reynaga, Sonia Chiasson, Paul C. van Oorschot. Heuristics for the evaluation of captchas on smartphones. In Shaun Lawson, Patrick Dickinson, editors, Proceedings of the 2015 British HCI Conference, Lincoln, United Kingdom, July 13-17, 2015. pages 126-135, ACM, 2015. [doi]
Abstract is missing.