1. Orbis Scientiae 1979;Nanopoulos,1978
2. 1979 Int. Symp. on Lepton and Photon Interactions, at High Energies;Wilczek,1979
3. M. Gell-Mann, Jerusalem Einstein Centennial Symposium, TH 2855-CERN;
4. S.L. Glashow, 1979 Cargèse Summer Institute, HUTP-79/A059;
5. A. Salam, 1979 EPS Meeting, IC/79/142.