Sorry again, but appreciate if you have still spare reprint of your recent paper : Dynamic simulation in Ag. Sys. My postal address is: M.Bannayan Univ. of Nottingham Sutton Bonington Dept. of PHES ( ENVS ) Leics, LE12 5RD UK Regards M.Bannayn University of Nottingham, Faculty of Agriculture, Department of Physiology and Environmental Sci. Tel: (44)- 115 - 9516260 - x: 8776 Fax: (44)- 115 - 9516261 E-mail: [log in to unmask] Homepage:http://www.ccc.nottingham.ac.uk/~sbxbam/mbahome.htm