1. Axford, W. I., 1964: Comments on “Generalization and critique of the wind-shear theory of sporadic E” by David Layzer. J. Geophys. Res., 69, 5093–5097.
2. Axford, W. I., and D. M. Cunnold, 1966: The wind-shear theory of temperate zone sporadic E. Radio Sci., 1, 191–198.
3. Cuchet, L., 1965: Étude de la formation des couches E-sporadiques dans une ionosphère a composition ionique complexe suivant la theorie des cisaillements de vents. Ann. Geophys., 21, 477–499.
4. Hines, C. O., et al., 1965: Physics of the Earth’s Upper Atmosphere. Englewood Cliffs, New Jersey, Prentice-Hall, 434 pp.
5. MacLeod, M. A., 1966: Sporadic E theory, I. Collision-geomag-netic equilibrium. J. Atmos. Sci., 23, 96–109.