@article{AIHPA_1989__50_3_369_0, author = {Fran\c{c}oise, J. P. and Ragnisco, O.}, title = {Matrix second-order differential equations and hamiltonian systems of quartic type}, journal = {Annales de l'I.H.P. Physique th\'eorique}, pages = {369--375}, publisher = {Gauthier-Villars}, volume = {50}, number = {3}, year = {1989}, zbl = {0695.58012}, mrnumber = {1017970}, language = {en}, url = {http://archive.numdam.org/item/AIHPA_1989__50_3_369_0/} }