“…Recall that if u n (t)= x(t&nc) is a spatially p-periodic traveling wave of (2.9), then x(t+pc)= x(t) and x : R Ä R satisfies the mixed functional differential equation (2.10). We now normalize the period of x by The Hopf bifurcation problem of (5.2) was discussed in Alexander and Auchmuty [2]. From now on, we will fix the positive integer p. Then, for given constants c and { and for a given 2?-periodic mapping y : R Ä R, we can define To apply the S 1 -bifurcation theory developed by Erbe, Geba, Krawcewicz and Wu [19] for parameterized mixed functional differential equations, we need to verify that D z F (z, {, c), the derivative of F with respect to the first argument, is an isomorphism at given (0, {, c).…”