1. Guenther, F., F. Munz, and H. Haussmann (I.G. Farben-industrie), U.S. Patent 1,932,180,1933.
2. Orelup, J.W., U.S. Patent 1,981,792, 1934.
3. Weil, J.K., N. Parris, and A.J. Stirton, JAOCS 47:91 (1970).
4. Lilienfeld, W.M. (Emulsol Corp.), U.S. Patent 2,490,459, 1949.
5. Noble, W.R., R.G. Bistline, Jr., and W.M. Linfield, Soap Cosmet. Chem. Spec. 48:38 (1972).