@article{AIHPC_1994__11_6_633_0,
     author = {Zhang, Dong},
     title = {An energy estimate of an exterior problem and a {Liouville} theorem for harmonic maps},
     journal = {Annales de l'I.H.P. Analyse non lin\'eaire},
     pages = {633--642},
     publisher = {Gauthier-Villars},
     volume = {11},
     number = {6},
     year = {1994},
     mrnumber = {1310625},
     zbl = {0834.58017},
     language = {en},
     url = {http://www.numdam.org/item/AIHPC_1994__11_6_633_0/}
}