REFERENCES
- ABHYANKAR , S. , 1958 , Trans. Inst. Radio Engrs, N.Y. , E.C.-7 , 268 ; 1959, Ibid., E.C.-8, 3 .
- CHOUDHURY , A. K. , and DAS , S. R. , 1964 , Indian J. Phys. , 28 , 125 .
- DE TROYE , N. C. , 1959 , Philips Res. Rep. , 14 , 000 .
- MCCLUSKEY , E. J. , Jr. , 1956 , Bell Syst. tech. J. , 35 , 1417 .
- QUINE , W. V. , 1952 , Amer. math. Month. , 59 , 521 .
- †Communicated by Dr. A. K. Choudhury.