@article{MAN_1933__108_159647,
     author = {H. Hopf and E. Pannwitz},
     title = {\"Uber stetige {Deformationen} von {Komplexen} in sich},
     journal = {Mathematische Annalen},
     pages = {433--465},
     publisher = {mathdoc},
     volume = {108},
     year = {1933},
     zbl = {59.1249.01},
     url = {http://geodesic.mathdoc.fr/item/MAN_1933__108_159647/}
}