1. M. Gourdin, 1974 Erice Lectures: Lepton and Hadron Structure, vol.12 A. Zichichi Editor, Academic Press (1975).
2. L. Wolfenstein, Talk given at the American Physical Society Meeting, Williamsburg (U.S.A.), September 1974.
3. K.V.L. Sarma, Talk given at the IInd High-Energy Physics Symposium, Visra-Bharati, Santiniketan (India), November 1974.
4. E.A. Paschos, Talk given at the Xe Rencontre de Moriond, Méribel (France), March 1975.
5. M. Gourdin, Rapporteur’s Talk at the European Physical Society Conference, Palermo (Italy), June 1975.