@article{1103052021,
author = {Hestenes, Magnus R.},
title = {Applications of the theory of quadratic forms in Hilbert space to the calculus of variations.},
journal = {Pacific J. Math.},
volume = {1},
number = {1},
year = {1951},
pages = { 525-581},
language = {en},
url = {http://dml.mathdoc.fr/item/1103052021}
}
Hestenes, Magnus R. Applications of the theory of quadratic forms in Hilbert space to the calculus of variations.. Pacific J. Math., Tome 1 (1951) no. 1, pp. 525-581. http://gdmltest.u-ga.fr/item/1103052021/