1. Kaufmann, P., Matsuura, O. T., and Fanto, P.: 1967a, Mackenzie University Annual Report GRAM-23, 3.27-3.46.
2. Kaufmann, P., Matsuura, O. T., and Marques Dos Santos, P.: 1967b, Icarus 7 (in press).
3. Kaufmann, P., Lopes, W., Schaal, R. E., and Fanto, P.: 1967c, Electron 4, 70.
4. Reder, F. H. and Viccione, D. M.: 1967, International Study of Ionospheric D-Layer and V.L.F. Propagation Phenomena. Institute for Exploratory Research, Deal, N.J., U.S.A.