Hilbert's Nineteenth Problem

This is a list of some references and links related to Hilbert's nineteenth problem.

1997	P. Marcellini: Some recent developments in the study of Hilbert's 19th and 20th problems. (Italian) Boll. Un. Mat. Ital. A (7) 11 no. 2, 323-352.
1976	E. Bombieri: Variational problems and elliptic equations. Proceedings of the Symposium in Pure Mathematics of the American Mathematical Society, Held at Northern Illinois University 1974, (edited by F.E.Browder), 525-535.
1900	D. Hilbert: Sind die Lösungen regulärer Variationsprobleme stets notwendig analytisch? Akad. Wiss. Göttingen 1900, 288-289. ps, pdf. English Translation

Hilbert's Problems, English. Hilberts Probleme, deutsch.