@article{MZ_1939__45_168850,
     author = {H., S\"ohngen},
     title = {Die {L\"osungen} der {Integralgleichung} g (x) ..................deren {Anwendung} in der {Tragfl\"ugeltheorie}},
     journal = {Mathematische Zeitschrift},
     pages = {245--264},
     year = {1939},
     volume = {45},
     zbl = {0020.36201},
     url = {http://geodesic.mathdoc.fr/item/MZ_1939__45_168850/}
}