[pdf] Volume 2, Methods of Mathematical Physics R. Courant, D. Hilbert

Since the first volume of this work came out in Germany in 1937, this book, together with its first volume, has remained standard in the field. Courant and Hilbert’s treatment restores the historically deep connections between physical intuition and mathematical development, providing the reader with a unified approach to mathematical physics. The present volume represents Richard Courant’s final revision of 1961.