1. H. Rotzsche, in M. Van Swaay (Editor), Preprints of the 4th International Gas Chromatography Symposium 1962, Butterworths, London, 1962, pp. 111 and 156.
2. H. Rotzsche and Institute of Silicone and Fluorocarbon Chemistry, Brit. Pat. 1018800, G.D.R. Pat 25747, F.R.G. Pat. 1137897, Fr. Pat. 1343831.
3. R. F. Kruppa, A. E. Coleman, U. S. Pat. 3 960521.
4. B. B. Wheals, J. Chromatogr.177, 263 (1979).
5. K. J. Welch, J. Chromatogr.177, 263 (1979).