KIM, S.; CHOI, S. DotCHA: An Interactive 3D Text-based CAPTCHA. Journal of Web Engineering, [S. l.], v. 18, n. 8, p. 837–864, 2020. DOI: 10.13052/jwe1540-9589.1884. Disponível em: https://journals.riverpublishers.com/index.php/JWE/article/view/956. Acesso em: 16 jul. 2024.