1. W. H. Bostick,Plasma Motors: The Propulsion of Plasma by Magnetic Means, IXth International Aeronautic Congress, Amsterdam 1958(Springer-Verlag, Berlin, Germany, 1959), pp. 794–808.
2. M. Abraham and R. Becker,Classical Electricity and Magnetism(Hafner Publishing Company, New York, 1932), p. 162.
3. W. R. Smythe,Static and Dynamic Electricity(McGraw-Hill Book Company, Inc., New York, 1950), 2nd ed., pp. 59 and 322.
4. H. Massey and E. Burhop,Electronic and Ionic Impact Phenomenon(Oxford University Press, London, England, 1952), pp. 14–15.
5. L. Spitzer, Jr.,Physics of Fully Ionized Gases(Interscience Publishers, Inc., New York, 1956), Chap. 4, p. 52.