Methods of mathematical physics / R. Courant and D. Hilbert. Methoden der mathematischen physik : English Courant, Richard, 1888-1972. Hilbert, David, 1862-1943, joint author. Mathematical physics. QA401 .C724 530.151 COM Includes bibliography. New York : Interscience Publishers, 1953-62. 1953-62. 1953 Text 2 v. eng engger