1. Ackerman, M.: 1971, in G. Fiocco (ed.), Mesospheric Models and Related Experiments, D. Reidel Publishing Company, Dordrecht-Holland, p. 149.
2. Aekerman, M.: 1972, Ann. Geophys. 28, 79.
3. Ackerman, M., Frimout, D., and Pastiels, R.: 1971, in F. Labuhn and R. L. Lüst (eds.), New Techniques in Space Astronomy, D. Reidel Publishing Company, Dordrecht-Holland, p. 251.
4. Ackerman, M. and Simon, P.: 1973, to be published.
5. Arvesen, J. C., Griffin, R. N., and Pearson, B. D.: 1969, Appl. Opt. 8, 2215.