Hazra, Suprokash, and Satish Shukla. “Some Generalizations of Kannan’s Theorems via σc-Function and Its Application”. Mathematical Modelling and Analysis 24, no. 4 (October 25, 2019): 530-549. Accessed April 12, 2025. https://jeelm.vgtu.lt/index.php/MMA/article/view/4716.