Yuan, Wenfa, Dongli Chen, and Pingan Wang. “A Strengthened Schwarz-Pick Inequality for Derivatives of the Hyperbolic Metric”. Tamkang Journal of Mathematics 37, no. 2 (June 30, 2006): 131–134. Accessed November 21, 2024. https://journals.math.tku.edu.tw/index.php/TKJM/article/view/157.