Using a recent critical point theorem due to Bonanno, the existence of a non-trivial solution for a class of systems of n fourth-order partial differential equations with Navier boundary conditions is established.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-ap105-1-6, author = {Shapour Heidarkhani}, title = {Non-trivial solutions for a class of (p1,...,pn)-biharmonic systems with Navier boundary conditions}, journal = {Annales Polonici Mathematici}, volume = {105}, year = {2012}, pages = {65-76}, zbl = {1261.35055}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ap105-1-6} }
Shapour Heidarkhani. Non-trivial solutions for a class of (p₁,...,pₙ)-biharmonic systems with Navier boundary conditions. Annales Polonici Mathematici, Tome 105 (2012) pp. 65-76. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ap105-1-6/