@article{00710127,
title = {Symmetric equilibria for a beam with a nonlinear elastic foundation.},
journal = {Portugaliae Mathematica. Nova S\'erie},
volume = {51},
year = {1994},
pages = {375-393},
zbl = {0815.34014},
language = {en},
url = {http://dml.mathdoc.fr/item/00710127}
}
Grossinho, M.R.; Ma, T.F. Symmetric equilibria for a beam with a nonlinear elastic foundation.. Portugaliae Mathematica. Nova Série, Tome 51 (1994) pp. 375-393. http://gdmltest.u-ga.fr/item/00710127/