1. Akabane, K., Nakajima, H., Ohki, K., Moriyama, F., and Miyaji, T.: 1973, Solar Phys. 33, 431.
2. Bougeret, J.: 1984, private communication.
3. Cliver, E. W.: 1984, private communication.
4. Cogdell, J. R.: 1972, Solar Phys. 22, 147.
5. Correia, E.: 1983, Ms.Thesis, INPE, Brazil.