Duren (mathematics, U. of Michigan) examines these univalent complex- valued harmonic functions of a complex variable, treating both the generalizations of univalent analytic functions and the connections with minimal surfaces. Duran's topics include general properties of harmonic mappings, harmonic mappings into convex regions, harmonic self-mappings of the disk, harmonic univalent functions, external problems, mapping problems, minimal surfaces and curvature of minimal surfaces, with particular attention to the Weierstrass-Enneper representation. Readers may wish to be prepared in complex analysis