1. E. Gavish andG. M. Friedman, Sedimentology, 20 (1973) 437.
2. D. Chester andH. Elderfield, Chem. Geol, 1 (1966) 277.
3. D. Northwood andD. Lewis, Canad. Mineral., 10 (1970) 216.
4. P. P. Mazzella, Ph. D. Thesis, Diss. Abstr. Int. B., 35 (1974) 759.
5. S. T. Silk andS. Z. Lewin, Advan. X-Ray Anal., 14 (1971) 29.