1. Verwey, E. J. W., I. Th. G. Overbeek, Theory of the Stability of Lyophobic Colloids (Amsterdam 1948).
2. Derjaguin, B. V., L. D. London, Acta Phys. Chim. USSR14, 633 (1941).
3. Hofmann, U., Kolloid-Z.125, 86 (1952).
4. Weiss, A., R. Fahn, U. Hofmann, Naturwissenschaften39, 351 (1952).
5. Hess, W. M., in: G. Kraus, Reinforcement of Elastomers, p. 192 (New York 1965).