1. Tattersall, R.L.O., Barnes, B.C., and Cartwright, N.E.: ‘Multipath transmission tests at 11, 20 and 37 GHz’, Propagation of radio waves at frequencies above 10 GHz, 1973), p. 65–69 IEE Conf. Publ. 98
2. Picquenard, A.: ‘Radio wave propagation’, (Macmillan 1974), p. 60–61