NAIDU, S. V. R. Fixed Point Theorems for Four Self-Maps on a Metric Space by Altering Distances. The Journal of the Indian Mathematical Society, [S. l.], v. 71, n. 1-4, p. 153–173, 2004. Disponível em: https://www.informaticsjournals.com/index.php/jims/article/view/22040. Acesso em: 29 apr. 2024.