1. S. Ramo and J. R. Whinnery, Fields and Waves in Modern Radio, 2d edition, Wiley, New York and London, 1960, pp. 283–284.
2. W. L. Stutzman and G. A. Thiele, Antenna Theory and Design,Wiley, New York, 1981, pp. 281–287 (spirals) and pp. 261–270 (helices).
3. J. D. Kraus, Antennas, McGraw-Hill, New York, 1950, Chapter 7.
4. J. L. Eaves and E. K. Reedy (editors), Principles of Modern Radar, Van Nostrand Reinhold, New York, 1987, pp. 9–11.
5. E. F. Knott, J. F. Shaeffer, and M. T. Tuley, Radar Cross Section, Artech House, Norwood, Mass., 1985, pp. 156–157.