1. Bhat, C.L., private communication.
2. Blumenthal, G.R., Faber, S.M., Primack, J.R., and Rees, M.J., 1984, Nature, 311, 517.
3. Boone, J., Cady, R., Cassiday, G.L., Elbert, J.E., Loh, E.C., Sokolsky, P.V., Steck, D., and Waserbeach, S., Proc. Cosmic Ray Workshop, University of Utah, 10–14.1.1983, p.268.
4. Dzikowski, T., Gawin, J., Grochalska, B., and Wdowczyk, J., 1980, ‘Origin of Cosmic Rays’, D. Reidel Publishing Company, p.327.
5. Dzikowski, T., Gawin, J., Grochalska, B., and Wdowczyk, J., 1981, Phil. Trans. R. Soc. Lond., A301, 641.