1. Ammon, H. L. (1970)Acta Crystallogr. B26, 451.
2. Bertinotti, F., Giacomello, G. & Liquori, A. M. (1954)Acta Crystallogr. 7, 808.
3. Brown, C. J. (1951)Acta Crystallogr. 4, 100.
4. Cromer, D. T. & Liberman, D. (1970) Los Alamos Scientific Laboratory, University of California Report LA-4403, UC-34.
5. Cruickshank, D. W. J., Bujosa, A., Lovell, F. M. & Truter, M. R. (1961) InComputing Methods and Phase Problem in Crystal Structure Analysis. Ed. R. Pepinsky and J. M. Robertson. New York: Pergamon Press.