1. A. Kastler:Compt. Rend.,231, 1462 (1950);A. Kastiee:Suppl. Nuovo Cimento,9, 315 (1952);R. Malvano:Suppl. Nuovo Cimento,9, 340 (1952).
2. G. L. Ragan:Microwave Transmission Circuits (New York, 1948), p. 375.
3. C. Ryter, R. Lackorx eR. Extermann:Helv. Phva. Acta,23, 539 (1950).