N. Shioji, EXISTENCE OF PERIODIC-SOLUTIONS FOR NONLINEAR EVOLUTION-EQUATIONS WITH PSEUDO MONOTONE-OPERATORS, Proceedings of the American Mathematical Society, 125(10), 1997, pp. 2921-2929
In this paper, we study the existence of T-periodic solutions for the
problem u'(t)+A(t)u(t) = 0, t is an element of R, where A(t) is a T-pe
riodic, pseudo monotone mapping from a reflexive Banach space into its
dual.