1. Partial Differential Equations of Parabolic Type;Friedman,1964
2. Theory of Reaction–Diffusion Equations;Ye,1990
3. Nonlinear Parabolic and Elliptic Equations;Pao,1992
4. Partial Differential Equations;Evans,1998
5. Monotone iterative technique for semilinear elliptic systems;Vatsala;Bound. Value Probl.,2005