Hi , i am new at this forum, i have a doubt about non linear differential equations systems; iīve been searching on some books about the solution of these systems, i wanted to know if there is some method which i can determinate the kind of system (damped, overdamped ...) and the response time, i couldnīt fine one, i hope anybody can help me, or can recomend a good book, please! the system is this:

dp1/dt = exp-(c + p1 + q1)

dp2/dt = exp-(c + p2 + q1)

dq1/dt = exp-(c + p1 + q1)

dq2/dt = exp-(c + p2 + q2)