Hi All, Who has the electronic document about Curves 5.3 Lavery,R. and Skelnar,H. (1989) J. Biomol. Struct. Dyn., 6, 655-667. It seems too old to find out. Regards, Yuguang Dr. Yuguang Mu School of Biological Sciences Nanyang Technological University Singapore 637616 Tel: 0065-63162885