1. Barut A. O., Bozić M. andMarić Z.,Ann. Phys. (N.Y.),214 (1992) 53.
2. Barut A. O. andBozić M.,Proceedings of the II International Wigner Symposium, Goslar, Germany, edited byDoebner H. D.,Scherer W. andSchroeck F. (World Scientific, Singapore) 1993.
3. Goldstein H.,Classical Mechanics (Addison-Wesley, Reading, Mass.) 1980.
4. Tomonaga S. I.,Quantum Mechanics (North-Holland) 1962.
5. Einstein A.,Verh. Dtsch. Phys. Ges.,19 (1917) 82.