@article{EJDE_2003__2003__a127,
     author = {Spadini,  Marco},
     title = {Harmonic solutions to perturbations of periodic separated variables {ODEs} on manifolds},
     journal = {Electronic journal of differential equations},
     year = {2003},
     volume = {2003},
     zbl = {1054.34074},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2003__2003__a127/}
}