S. . G. Rad and H. Rahimi, “Common Fixed-Point Theorems and c-distance in Ordered Cone Metric Spaces”, Ukr. Mat. Zhurn., vol. 65, no. 12, pp. 1667–1680, Dec. 2013, Accessed: Dec. 06, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/2545