1. ‘Predicting long-term operational parameters of high-frequency skywave telecommunications systems’, Technical Report, ERL-110-ITS-78, Environmental Science Services Administration, US Dept. of Commerce, May, 1969
2. Stratton, J.A.: Electromagnetic Theory, (McGraw-Hill, New York 1941)
3. Jordan, E.C.: Electromagnetic Waves and Radiating Systems, (Prentice Hall, Englewood Cliffs, N.J. 1968), p. 333–338