Nazam M., Hussain N., Hussain A., and Arshad M. “Fixed Point Theorems for Weakly Beta-Admissible Pair of F-Contractions With Application”. Nonlinear Analysis: Modelling and Control, Vol. 24, no. 6, Nov. 2019, pp. 898–918, doi:10.15388/NA.2019.6.4.