1. Birks L. S. (1963) Electron probe microanalysis (John Wiley, New York).
2. Brewer R. (1963) Fabric and Mineral Analysis of Soils (John Wiley, New York).
3. (1961) Methods of testing soils for civil engineering purposes, B.S. 1377. British Standards Institution.
4. The mineralogy and phase equilibrium of Keuper Marl;Davis;Q. Jl Engng. Geol.,1967
5. Dumbleton M. J. West G. (1966) Studies of the Keuper Marl: mineralogy. R.R.L. Report no. 40. 25.