@article{MAN_1954__127_160387,
     author = {H. Wittich},
     title = {Zur {Theorie} der {Riccatischen} {Differentialgleichung.}},
     journal = {Mathematische Annalen},
     pages = {433--440},
     publisher = {mathdoc},
     volume = {127},
     year = {1954},
     zbl = {0055.08005},
     url = {http://geodesic.mathdoc.fr/item/MAN_1954__127_160387/}
}