Über die Konvergenz des Verfahrens vonGrammel und seine mögliche Erweiterung

Summary The paper deals with the convergence ofR. Grammel's method for the solution of boundary-eigenvalue-problems. It is further shown thatGrammel's method can be extended to the case where it is difficult to find the exactGreen function. In this case one may use a different, relatedGreen function if one adds certain supplemental terms to the properGrammel equations.