“…By Theorem 1.1, 2sq + l − (s + c) > 0 and 2sq + r − (s + c) < 0, hence, since 0 < q + r , q + l < 1, we conclude that ∂q + r /∂q + l < 0. Recently, M 5 -traveling wave solutions for system (1) have been investigated by Cruz-García et al [3]. Using Lagrange's interpolation method, the authors derived an exactly solvable approximate equation which yields analytical approximations for the standing and traveling waves.…”