@article{GDZPPN002273470,
title = {Determination of affine and metric spaces by their differential invariants},
journal = {Mathematische Annalen},
volume = {101},
year = {1929},
pages = {713-728},
zbl = {55.1028.01},
url = {http://dml.mathdoc.fr/item/GDZPPN002273470}
}
Thomas, T.Y. Determination of affine and metric spaces by their differential invariants. Mathematische Annalen, Tome 101 (1929) pp. 713-728. http://gdmltest.u-ga.fr/item/GDZPPN002273470/