@article{MAN_1967__172_161586,
     author = {J.W. Baker},
     title = {On a {Generalised} {Open-Mapping} {Theorem}},
     journal = {Mathematische Annalen},
     pages = {217--221},
     publisher = {mathdoc},
     volume = {172},
     year = {1967},
     zbl = {0231.22001},
     url = {http://geodesic.mathdoc.fr/item/MAN_1967__172_161586/}
}