1. S.C. Majumdar et al., Atlas of tropospheric radio refractivity over the Indian subcontinent, New Delhi, National Physical Laboratory, 1977.
2. P.F. Parter,Communication system design:line-of-sight and tropo-scatter systems, New York, McGraw-Hill, 1972.
3. M Dolukharov,Propagation of radio waves, Moscow. Mir Publishers, 1971.
4. Properties of 400 Mcps Long-Distance Tropospheric Circuits