Chacón, Gerardo R., Renato Colucci, and Daniele D’Angeli. “Density of Backward Paths on the Julia Set of a Semigroup”. Sarajevo Journal of Mathematics 10, no. 1 (June 4, 2024): 77–85. Accessed April 21, 2026. https://sjm.ba/index.php/sjm/article/view/163.