@article{JDM_1905__14_144972,
     author = {Otto Knopf},
     title = {Ernst {Abbe.}},
     journal = {Jahresbericht der Deutschen Mathematiker-Vereinigung},
     pages = {217--230},
     publisher = {mathdoc},
     volume = {14},
     year = {1905},
     url = {http://geodesic.mathdoc.fr/item/JDM_1905__14_144972/}
}