@article{JRAM_1900__122_149092,
     author = {E. Gr\"unfeld},
     title = {Zur {Theorie} der einer linearen {Differentialgleichung} n-ter {Ordnung} adjungirten {Differentialgleichungen.}},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {43--52},
     publisher = {mathdoc},
     volume = {122},
     year = {1900},
     zbl = {31.0341.01},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1900__122_149092/}
}