@article{AIHPC_1993__10_6_605_0, author = {Long, Yiming}, title = {The minimal period problem of classical hamiltonian systems with even potentials}, journal = {Annales de l'I.H.P. Analyse non lin\'eaire}, pages = {605--626}, year = {1993}, publisher = {Gauthier-Villars}, volume = {10}, number = {6}, mrnumber = {1253604}, zbl = {0804.58018}, language = {en}, url = {https://www.numdam.org/item/AIHPC_1993__10_6_605_0/} }