@article{AIHPC_2007__24_4_589_0,
     author = {Chen, Chao-Nien and Hu, Xijun},
     title = {Maslov index for homoclinic orbits of hamiltonian systems},
     journal = {Annales de l'I.H.P. Analyse non lin\'eaire},
     pages = {589--603},
     publisher = {Elsevier},
     volume = {24},
     number = {4},
     year = {2007},
     doi = {10.1016/j.anihpc.2006.06.002},
     mrnumber = {2334994},
     language = {en},
     url = {http://www.numdam.org/articles/10.1016/j.anihpc.2006.06.002/}
}