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Especially among Japanese mathematicians Mitio Nagumo (1905-1995) is regarded as one of the greatest pioneers in research on differential equations. However, so far most of his papers have only been published in Japanese journals and were unavailable in the West. This Collected Papers volume contains practically all mathematical papers Nagumo wrote in languages other than Japanese and will be a basic reference volume and essential working tool for every library and for many active mathematicians in differential equations, topology and differential geometry. In addition, papers that were originally published in Japanese were translated especially for this edition. There are three main sections in this book, devoted to ordinary differential equations, partial differential equations and other equations. Each section is accompanied by a detailed commentary provided by the editors.

S. Agmon: Asymptotic formulas with remainder estimates for eigenvalues of elliptic operators.- J. Bokobza-Haggiag: Une definition globale des operateurs pseudo-differentiels sur une variete differentiable.- L. Boutet de Monvel: Pseudo-differential operators and analytic function.- A. Calderon: A priori estimates for singular integral operators.- B.F. Jones: Characterization of spaces of Bessel potentials related to the heat equation.- J.J. Kohn: Pseudo-differential operators and non-elliptic problems.- R.T. Seeley: Topics in pseudo-differential operators.- I.M. E. Shamir: Boundary value problems for elliptic convolution systems.- Singer: Elliptic operators on manifolds.