On the "triangular" inequality in the theory of two-phase random media. Annual of Sofia University St. Kliment Ohridski. Faculty of Mathematics and Informatics, [S. l.], v. 89, p. 159–166, 1997. Disponível em: https://annual.uni-sofia.bg/index.php/fmi/article/view/364. Acesso em: 15 dec. 2025.