@article{01866011, title = {Two-distance preserving functions.}, journal = {Beitr\"age zur Algebra und Geometrie}, volume = {43}, year = {2002}, pages = {557-564}, zbl = {1018.51009}, language = {en}, url = {http://dml.mathdoc.fr/item/01866011} }
Khamsemanan, Nirattaya; Connelly, Robert. Two-distance preserving functions.. Beiträge zur Algebra und Geometrie, Tome 43 (2002) pp. 557-564. http://gdmltest.u-ga.fr/item/01866011/