ASYMPTOTIC EXPERSSION OF THE SOLUTION OF GENERAL BOUNDARY VALUE PROBLEN FOR HIGHER ORDER ELLIPTIC EQUATION WITH PERTURBATION BOTH IN BOUNDARY AND IN OPERATOR

In this paper basing on (1) and (2),we study thesingular perturbation of general boundary value problemfor higher order elliptic equation with perturbationboth in the boundary and in the operator,so as to es-tablish the asymptotic expression involving two para-meters.Thus,the iterative process of finding theasymptotic solution is derived and the estimation ofthe remainder term is given out,we extend and improvethe previously published papers.