“…Consequently, the sequence {x n } generated by (1.5) may fail to converge strongly (see Section 4 in [49]). The gradient projection algorithm (1.5) has been studied extensively by many authors, see for instance [8,9,19,20,21,44,49] and reference therein. In 2000, Moudafi [29] introduced the viscosity approximation method for approximating fixed points of nonexpansive mappings.…”