1. B. Zumino, lectures at the Cargese Summer Institute, July 1972, CERN TH 1550 (1972).
2. J.C. Taylor, An introduction to gauge fields and renormalizable theories of charged vector mesons, Rutherford Laboratory preprint, RPP/T/29 (1972).
3. L.N. Sehgal, Unified theories of weak and electromagnetic interactions: an elementary introduction, Aachen preprint, PITHA-68 (1973).
4. A. De Rujula, An elementary introduction to the unified theories of weak and electromagnetic interactions. Harvard preprint (1973)
5. Riazuddin, An introduction to spontaneously broken gauge theories of weak and electromagnetic interactions,Darestury preprint (1973)