@article{MZ_1930__31_168199,
     author = {D. Enskog},
     title = {\"Uber die {Hauptfunktionen} unsymmetrischer {Kerne}},
     journal = {Mathematische Zeitschrift},
     pages = {601--610},
     publisher = {mathdoc},
     volume = {31},
     year = {1930},
     zbl = {56.0338.01},
     url = {http://geodesic.mathdoc.fr/item/MZ_1930__31_168199/}
}