@article{JDM_1958__60_146433,
     author = {E. Kamke and K. Zeller},
     title = {Konrad {Knopp.}},
     journal = {Jahresbericht der Deutschen Mathematiker-Vereinigung},
     pages = {43--49},
     publisher = {mathdoc},
     volume = {60},
     year = {1958},
     url = {http://geodesic.mathdoc.fr/item/JDM_1958__60_146433/}
}