ughade, manoj, P. L. Sanodia, Arvind Gupta, and Amit Kumar Pandey. “QUADRUPLE FIXED POINT THEOREMS FOR (α,ψ) - CONTRACTIVE TYPE MAPPINGS IN PARTIALLY ORDERED METRIC SPACES”. Journal of Global Research in Mathematical Archives(JGRMA) 2, no. 6 (March 18, 2015): 27–43. Accessed July 7, 2025. https://www.jgrma.com/index.php/jgrma/article/view/225.