V. Malliga Devi, R. Mohan Raj, M. Jeyaraman, and M. Kayalvizhi. “Common Fixed Point Theorem in Intuitionistic Fuzzy 3-Metric Spaces”. International Journal of Mathematics And Its Applications, vol. 4, no. 2 - D, June 2016, pp. 103-8, https://ijmaa.in/index.php/ijmaa/article/view/1073.