SU(3) x SU(2) x U(1) and beyond : proceedings of the XIIIth GIFT International Seminar on Theoretical Physics and Xth International Winter Meeting on Fundamental Physics, 28 Jan.-6 Feb., 1982, Masella (Girona), Spain / editors, A. Ferrando, J.A. Grifols, A. Méndez. International Seminar on Theoretical Physics (13th : 1982 : Masella, Spain) Ferrando, A. Grifols, J. A. Méndez, A. International Winter Meeting on Fundamental Physics (10th : 1982 : Masella, Spain) Symmetry (Physics) Congresses. 530.1 19 FES Includes bibliographical references. Singapore : World Scientific, c1983. c1983. 1983 Text 506 p. : eng