Courant, Richard, 1888-1972. Dirichlet's principle, conformal mapping, and minimal surfaces R. Courant ; with an Appendix by M. Schiffer - New York Interscience Publishers 1950 - xiii, 330 p. : diagrs. ; 24 cm. Bibliography: p. 245-248, 319-323. Subjects--Topical Terms: Surfaces, Representation of