@article{GDZPPN002391708, title = {A generalization of the ordered group of integers.}, journal = {Mathematische Zeitschrift}, volume = {78}, year = {1962}, pages = {21-31}, zbl = {0146.25802}, url = {http://dml.mathdoc.fr/item/GDZPPN002391708} }
Venkataraman, R.; Sankaran, N. A generalization of the ordered group of integers.. Mathematische Zeitschrift, Tome 78 (1962) pp. 21-31. http://gdmltest.u-ga.fr/item/GDZPPN002391708/