1. Allen, C.W., Astrophysical Quantities, 1976, Athlone Press.
2. Bahcall, J.N., Soneira, R.M., 1980, Ap.J. Supp., 44, 73.
3. IRAS Explanatory Supplement, 1985, edited by Beichman, C.A., Neugebauer, G., Habing, H.J., Clegg, P.E., Chester, T.J., The United States Government Printing Office.
4. Habing, H., these proceedings, page 239.
5. Lonsdale, C.J., Persson, S.E., Matthews, K., 1984, Ap. J., 287, 95.