Quantum Field Theory Proceedings of the Ringberg Workshop Held at Tegernsee, Germany, 21-24 June 1998 On the Occasion of Wolfhart Zimmermann's 70th Birthday - Breitenlohner, Peter; Breitenlohner, Peter; Maison, Dieter; Maison, Dieter (Springer Berlin Heidelberg : Imprint: Springer, 2000)