@article{02099170,
title = {Critical point theory for nonsmooth energy functionals and applications.},
journal = {Acta Mathematica Universitatis Comenianae. New Series},
volume = {71},
year = {2002},
pages = {147-155},
zbl = {1108.35041},
language = {en},
url = {http://dml.mathdoc.fr/item/02099170}
}
Halidias, N. Critical point theory for nonsmooth energy functionals and applications.. Acta Mathematica Universitatis Comenianae. New Series, Tome 71 (2002) pp. 147-155. http://gdmltest.u-ga.fr/item/02099170/