@article{MZ_1995__218_4_174727,
     author = {Piero D'Ancona},
     title = {A note on a theorem of {J\"orgens.}},
     journal = {Mathematische Zeitschrift},
     pages = {239--252},
     publisher = {mathdoc},
     volume = {218},
     number = {4},
     year = {1995},
     zbl = {0816.35086},
     url = {http://geodesic.mathdoc.fr/item/MZ_1995__218_4_174727/}
}