変分法
Dacorogna, Bernard. Introduction to the Calculus of Variations (3rd Edition), 2014, World Scientific Publishing, ISBN 978-1-78326-551-0. Introduction
Bolza, O.: Lectures on the Calculus of Variations. Chelsea Publishing Company, 1904, available on Digital Mathematics library . 2nd edition republished in 1961, paperback in 2005, ISBN 978-1-4181-8201-4.
Cassel, Kevin W.: Variational Methods with Applications in Science and Engineering, Cambridge University Press, 2013.
Clegg, J.C.: Calculus of Variations, Interscience Publishers Inc., 1968.