Acupuncture for episodic tension-type headache: a multicentre randomized controlled trial. - White, AR; Resch, K-L; Chan, JCK; Norris, CD; Modi, SK; Patel, JN; Ernst, E; White, A R; Chan, J C; Norris, C D; Modi, S K; Patel, J N (Cephalalgia, 2000)