1. Cronan, D. S., and Tooms, J. S., Deep Sea Res., 16, 335 (1969).
2. Straczec, J. A., Horen, A., Ross, M., and Warshaw, C. W., Am. Miner., 45, 1174 (1960).
3. Parker, F. L., Rep. Swedish Deep Sea Expedition, 1947–1948 8, 219 1958.
4. Herman, Y., Proc. second Planktonic Conf. (edit. by Farinacci, A.), (Technoscienza, Rome, 1971).
5. Wiseman, J. D. H., Rep. Swedish Deep Sea Expedition, 1947–48 7, 287 1965.