1. Ives, J. D., Andrews, J. T., and Barry, R. G., Naturwissenschaften, 62, 118 (1975).
2. Adam, D. P., Quat. Res., 5, 161 (1975).
3. Thompson, H. A., in Science, History and Hudson Bay, Pt 1, ch. 5 (Queen's Printer, Ottawa, 1968).
4. Atlas of World Water Balance and Water Resources of the Earth (USSR National Committee for the International Hydrological Decade, Leningrad, 1974).
5. Mahaffy, M. A., thesis, Univ. Colorado, Boulder (1974).