BHALERAO, Archana; RADE, Lina. A Basic Survey of CAPTCHA :Application and Challenges. International Journal of Scientific Research in Computer Science and Engineering, [S. l.], v. 6, n. 1, p. 1–5, 2018. Disponível em: https://ijsrcse.isroset.org/index.php/j/article/view/213. Acesso em: 4 apr. 2025.