Kaelo, P., Narayanan, S., & Thuto, M. (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), 177–185. https://doi.org/10.11121/ijocta.01.2017.00339