@article{GDZPPN002051656,
title = {Zur Theorie der Bewegungsgruppen.},
journal = {Commentarii mathematici Helvetici},
volume = {7},
year = {1934},
pages = {159-184},
language = {de},
url = {http://dml.mathdoc.fr/item/GDZPPN002051656}
}
Burckhardt, J.J. Zur Theorie der Bewegungsgruppen.. Commentarii mathematici Helvetici, Tome 7 (1934) pp. 159-184. http://gdmltest.u-ga.fr/item/GDZPPN002051656/