SKORDEV, D. On the average delay of the detection of cyclic loops. Ann. Sofia Univ. Fac. Math. and Inf., [S. l.], v. 85, p. 13–34, 1993. Disponível em: https://admin.uni-sofia.bg/index.php/fmi/article/view/449. Acesso em: 16 jan. 2025.