@article{PIM_1953_S_S_V_05_a0,
     author = {T. P. Angelitch},
     title = {Eine {Bemerkung} {Zu} {Den} {Gleichungen} {Von} {Beltrami-Michell}},
     journal = {Publications de l'Institut Math\'ematique},
     pages = {1 },
     publisher = {mathdoc},
     volume = {_S_S_V},
     number = {05},
     year = {1953},
     url = {http://geodesic.mathdoc.fr/item/PIM_1953_S_S_V_05_a0/}
}