Atanassov, Krassimir, and Janusz Kacprzyk. “Bipolar Fuzzy Sets Are Intuitionistic Fuzzy Sets”. Proceedings of the Bulgarian Academy of Sciences 77, no. 12 (December 25, 2024): 1752–1756. Accessed January 15, 2025. https://proceedings.bas.bg/index.php/cr/article/view/658.