Description: Part of proof of Lemma E in Crawley p. 113, 5th paragraph on p. 114, line 3. D , F , N , Y , G , O represent s_2, f(s), f_s(r), t_2, f(t), f_t(r). We prove that if r <_ s \/ t, then f_t(r) = f_t(r). (Contributed by NM, 14-Nov-2012)