@article{GDZPPN002256398,
title = {Ueber Tripelsysteme},
journal = {Mathematische Annalen},
volume = {49},
year = {1897},
pages = {101-112},
language = {de},
url = {http://dml.mathdoc.fr/item/GDZPPN002256398}
}
Heffter, Lothar. Ueber Tripelsysteme. Mathematische Annalen, Tome 49 (1897) pp. 101-112. http://gdmltest.u-ga.fr/item/GDZPPN002256398/