@article{GDZPPN002066580, title = {A uniqueness theorem for Zn-periodic variational problems.}, journal = {Commentarii mathematici Helvetici}, volume = {62}, year = {1987}, pages = {511-531}, zbl = {0634.49018}, url = {http://dml.mathdoc.fr/item/GDZPPN002066580} }
Bangert, V. A uniqueness theorem for Zn-periodic variational problems.. Commentarii mathematici Helvetici, Tome 62 (1987) pp. 511-531. http://gdmltest.u-ga.fr/item/GDZPPN002066580/