@article{1102977527, author = {Helfenstein, H. G.}, title = {Local isometries of flat tori.}, journal = {Pacific J. Math.}, volume = {35}, number = {3}, year = {1970}, pages = { 113-117}, language = {en}, url = {http://dml.mathdoc.fr/item/1102977527} }
Helfenstein, H. G. Local isometries of flat tori.. Pacific J. Math., Tome 35 (1970) no. 3, pp. 113-117. http://gdmltest.u-ga.fr/item/1102977527/