The Newton polygon approach for boundary value problems with general boundary conditions
R. Denk and L. Volevich
Abstract. 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.
Spectral and Evolutionary Problems 10 (2000), 115-121.
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