A Class of modified BFGS Methods with Function Value Information for unconstrained Optimization. - Hao Liu; Haijun Wang; Xiao-Yan Qian; Qing-Sheng Shi (Asia Pac. J. Oper. Res., 2013)

A conjugate gradient method with sufficient descent property. - Hao Liu; Haijun Wang; Xiao-Yan Qian; Feng Rao (Numer. Algorithms, 2015)