1. (a) Martin, J.: 1978, “Communication Satellite Systems”, published by Prentice Hall.
2. Sachdev, D.K.: 1981, “Satellite Communication Technology-Challenges for the 1980s”, J of Spacecraft and Rockets, Vol.18, No.2, pp.110-117.
3. (c) Soop, M.: 1983, “Introduction to Geostationary Orbits”, ESA SP-1053.