1. FMI (Physics and Mathematics Department), Mid-Sweden University, S 851-70 Sundsvall, Sweden.
2. Institute for Biomedical Computing, Washington University, Campus Box 8036, 700 S. Euclid Avenue, St. Louis, MO 63110.
3. University of Canterbury, Private Bag 4800, Christchurch, New Zealand.
4. Computer Science Department, Massey University, PO Box 11-222, Palmerston North, New Zealand.
5. Institute of Molecular BioSciences, Massey University, PO Box 11-222, Palmerston North, New Zealand.