1. Byron, F.W., and Fuller, R.W.: Mathematics of classical and quantum physics, (Addison-Wesley 1969),2,
2. Sucher, M.: Fox, J., Handbook of microwave measurements, (Polytechnic Press of the Polytechnic Institute of Brooklyn 1963),1,
3. Balkanski, M., Handbook on semiconductors, (North-Holland 1980),2,