Communications on Pure and Applied Mathematics · 1974 · 47 citations · 2 references
Natural SciencesMathematicsDifferential EquationsBoundary ConditionsPartial Differential EquationsSystems Of Differential EquationsElliptic Boundary-value ProblemsElliptic Partial Differential EquationsPseudodifferential OperatorsSecond-order Differential EquationsSturm - Liouville Theory
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