1. W. Heisenberg:Zeits. f. Phys.,101, 533 (1936).
2. A. Pais:Weak Interactions at High Energies, inTheoretical Physics (Vienna, 1963).
3. See, for example,R. E. Marshak:Meson Physics, Chapter 7 (New York, 1952).
4. S. Treiman:Structure of the Weak Interactions, inLecture Notes on Weak Interactions, edited byC. Fronsdal (New York, 1963).
5. T. D. Lee andC. N. Yang:Phys. Rev.,119, 1410 (1960).