@article{EJDE_2015__2015__a84,
     author = {Timoumi,  Mohsen},
     title = {Existence of periodic solutions for sub-linear first-order {Hamiltonian} systems},
     journal = {Electronic journal of differential equations},
     year = {2015},
     volume = {2015},
     zbl = {1353.34049},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2015__2015__a84/}
}