
Odell,Garrett M and Segel,Lee A

Biograph is an interactive program that computes
numerically, then graphs solutions to systems of ordinary differential
equations (ODE's) and difference equations. The program is capable
of solving systems of n simultaneous DE's or difference equations.
(from the review of the program
by QUANTITATIVE CURRICULUM FOR LIFE SCIENCE STUDENTS)

Look at the review of the program by
QUANTITATIVE CURRICULUM FOR LIFE SCIENCE STUDENTS. 
