BILGE, Ayse Humeyra, and Yunus OZDEMIR. “The Critical Point of a Sigmoidal Curve”. Studia Universitatis Babeș-Bolyai Mathematica 65, no. 1 (March 6, 2020): 77–91. Accessed February 4, 2026. https://studia.reviste.ubbcluj.ro/index.php/subbmathematica/article/view/2417.