@article{PPN236008730+dmdlog158, title = {Bestimmung der Normalelemente}, booktitle = {Theoretische Astronomie Bd. 7}, series = {GDML\_Books}, year = {1906}, pages = {559}, url = {http://dml.mathdoc.fr/item/PPN236008730+dmdlog158} }
(éd.). Bestimmung der Normalelemente, dans Theoretische Astronomie Bd. 7, GDML_Books, (1906), p. 559. http://gdmltest.u-ga.fr/item/PPN236008730+dmdlog158/