1. Ruetz, W., Dissertation, TH München (1964).
2. Feldman, R. F., Sereda, P. J., J. appl. Chem.,14, 87 and 93 (1964).
3. Richartz, W., Locher, F. W., Zement-Kalk-Gips,18, 449 (1965).
4. Powers, T. C., Proceedings of the fourth international symposium on the chemistry of cement, Washington (1960), p. 577.
5. Powers, T. C., International conference on the structure of concrete, London (1965), Paper G 1.