D. Bainov et al., MONOTONE ITERATIVE METHOD FOR SEMILINEAR ELLIPTIC-SYSTEMS OF OPERATOR-DIFFERENTIAL EQUATIONS, Israel Journal of Mathematics, 92(1-3), 1995, pp. 285-293
Existence of extremal solutions of semilinear elliptic systems of oper
ator-differential equations is proved. The extremal solutions are obta
ined via monotone iterates.