Sun, Yan, and Ravi P. Agarwal. “EXISTENCE OF FIXED POINT FOR NONLINEAR OPERATOR IN PARTIALLY ORDERED METRIC SPACES”. Advances in Differential Equations and Control Processes 30, no. 2 (April 14, 2023). Accessed February 11, 2025. https://ojs.acad-pub.com/index.php/ADECP/article/view/2406.