@article{JDM_1918__26_145526,
     author = {Gertrud Klein},
     title = {Zur {Eulerschen} {L\"osung} des isoperimetrischen {Problems.}},
     journal = {Jahresbericht der Deutschen Mathematiker-Vereinigung},
     pages = {344--348},
     publisher = {mathdoc},
     volume = {26},
     year = {1918},
     zbl = {46.0766.01},
     url = {http://geodesic.mathdoc.fr/item/JDM_1918__26_145526/}
}