@article{MZ_1942__48_168984,
     author = {H. Seifert},
     title = {Zur asymptotischen {Integration} von {Differentialgleichungen}},
     journal = {Mathematische Zeitschrift},
     pages = {173--192},
     year = {1942},
     volume = {48},
     zbl = {0026.40301},
     url = {http://geodesic.mathdoc.fr/item/MZ_1942__48_168984/}
}