Local Bounds for Solutions of Higher Order Nonlinear Elliptic Partial Differential Equations. Kjell-Ove Widman — 1971 Mathematische Zeitschrift
Inequalities for the Green Function and Boundary Continuity of the Gradient of Solutions of Elliptic Differential Equations. Kjell-Ove Widman — 1967 Mathematica Scandinavica
Asymptotic Behavior of Solutions of Parabolic Equations with Discontinuous Coefficients. Kjell-Ove Widman — 1970 Mathematica Scandinavica
Some Regularity Results for Quasilinear Elliptic Systems of Second Order. Stefan Hildebrandt; Kjell-Ove Widman — 1975 Mathematische Zeitschrift
On the Hölder continuity of weak solutions of quasilinear elliptic systems of second order Stefan Hildebrandt; Kjell-Ove Widman — 1977 Annali della Scuola Normale Superiore di Pisa - Classe di Scienze
Harmonic mappings into Riemannian manifolds with non-positive sectional curvature. Helmut Kaul; Stefan Hildebrandt; Kjell-Ove Widman — 1975 Mathematica Scandinavica