1. See, for example, L. Spitzer, Jr.,The Physics of Fully Ionized Gases(Interscience Publishers, Inc., New York, 1956), p. 55, for a discussion and further references.
2. Harold Grad, inThe Magnetohydrodynamics of Conducting Fluids, D. Bershader, Editor (Stanford University Press, Palo Alto, California, 1959). Further references to related work are given there.
3. We shall use the notation V⊥ = e0×(V×e0) for other vectors as well.