1. Anderson, G.F.: 1966, Thesis, University of Colorado.
2. Athay, R.G. and Moreton, G.E.: 1961, Astrophys. J. 133, 935.
3. Bahng, J. and Schwarzschild, M.: 1963, Astrophys. J. 137, 901.
4. Billings, D.E.: 1967, A Guide to the Solar Corona. Academic Press, New York.
5. Dodson, H.W. and Hedeman, R.E.: 1964, AAS-NASA Symposium on the Physics of Solar Flares (ed. by W.H. Hess). U.S. Government Printing Office, Washington D.C.