@article{GDZPPN002051621,
title = {Ueber symmetrische Monoide und Kegel.},
journal = {Commentarii mathematici Helvetici},
volume = {7},
year = {1934},
pages = {133-143},
zbl = {0007.32305},
url = {http://dml.mathdoc.fr/item/GDZPPN002051621}
}
Emch, Arnold. Ueber symmetrische Monoide und Kegel.. Commentarii mathematici Helvetici, Tome 7 (1934) pp. 133-143. http://gdmltest.u-ga.fr/item/GDZPPN002051621/