Bibliography
- Further information about variational principles can be obtained by consulting the following books
- Courant , R. and Robbins , H. 1941 . What is Mathematics? , New York : Oxford University Press . Chap. VII
- Lanczos , C. 1963 . The Variational Principles of Mechanics , (2nd edn.) , University of Toronto Press .
- Lyusternik , L. A. 1964 . Shortest Paths: Variational Problems , Oxford : Pergamon .
- Moiseiwitsch , B. L. 1966 . Variational Principles , London : Wiley‐Interscience .
- Yourgrau , W. and Mandelstam , S. 1968 . Variational Principles in Dynamics and Quantum Theory (3rd edn.) , London : Pitman .