Kaelo, Pro, Sindhu Narayanan, and M.V. Thuto. 2017. “A Modified Quadratic Hybridization of Polak-Ribiere-Polyak and Fletcher-Reeves Conjugate Gradient Method for Unconstrained Optimization Problems”. An International Journal of Optimization and Control: Theories & Applications (IJOCTA) 7 (2):177-85. https://doi.org/10.11121/ijocta.01.2017.00339.