1. Rieger, B., Plach, H. J. and Naemura, S. 1991.Proceedings of the 5th Liquid Crystal Seminar, 81Merck Japan Ltd. see also Plach, H. J., Weber, G., and Rieger, B., 1990,SID Int. Disp. Conf., p. 136.
2. Vetter, P. 1991. Belgium: University of Ghent. Ph.D. Thesis
3. Dijon, J., Ebel, C., Vauchier, C., Baume, F., Clerc, J.F., Estor, M., Leroux, T., Maltese, P. and Mulatier, L. 1988.SID 1988 Digest246