The Newton polygon approach for boundary value problems with general boundary conditions
Robert Denk, Leonid R. Volevič · KOPS (University of Konstanz) · 2000
A large class of parameter-dependent elliptic problems was introduced in the sixties by Agmon and Agranovich-Vishik. Some important examples, however, cannot be treated with the classical methods, for instance, singularly perturbed problems and the resolvent of Douglis-Nirenberg systems. This paper gives a short survey on the results of the so-called Newton polygon approach applied to singularly perturbed boundary value problems and to systems of mixed order depending in a specific way on a complex parameter.