@article{JRAM_1898__119_149039,
     author = {Georg Wallenberg},
     title = {Ueber nichtlineare homogene {Differentialgleichungen} zweiter {Ordnung.}},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {87--113},
     publisher = {mathdoc},
     volume = {119},
     year = {1898},
     zbl = {29.0280.03},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1898__119_149039/}
}