“…Under the assumptions (H1)-(H3), it follows from Ma and Wu [32] and Wang et al [43] that (1.2) admits a strictly increasing traveling wave front ϕ (x + ct) satisfying ϕ (−∞) = 0 and ϕ (+∞) = K with wave speed c ∈ R. When c = 0, we know from [44] that for any (θ 1 , θ 2 ) ∈ R 2 , there exists a unique entire solution U (x, t) := U (x, t; θ 1 , θ 2 ) with 0 < U (x, t) < K for all (x, t) ∈ R 2 such that…”