Survivals of two cooperating species of animals

The purpose of this paper is to give conditions for the existence and uniqueness positive solution a rather general type elliptic system Dirichlet problem on bounded domain Ω in R n . Also considered are effects perturbations coexistence state uniqueness. techniques used super-sub solutions method, eigenvalues operators, maximum principles, spectrum estimates, inverse function theory, theory. arguments also rely some detailed properties logistic equations. These results yield an algebraically computable criterion cooperating species animals many biological models.