1. Abramowitz , M. I. A. Stegun ( Handbook of Mathematical Functions, Appl. Math. Ser. 55 National Bureau of Standards Washington, D.C. 1964
2. On the theory of radio wave propagation over inhomogeneous earth;Furutsu;J. Res. Natl. Bur. Stand., Sect. D,1963
3. Path integrals for solving some electromagnetic edge diffraction problems;Lee;J. Math. Phys.,1978
4. Meeks , M. L. R. W. Reed ( Multiple diffraction effects in VHF propagation, Proc. IEE Conf. Antennas Propag., Part 2 154 157 Propagation York, UK 1981
5. Double knife-edge diffraction in field-strength predictions;Millington;Proc. IEE Monogr.,1962