@article{01140287, title = {A subset of metric preserving functions.}, journal = {International Journal of Mathematics and Mathematical Sciences}, volume = {21}, year = {1998}, pages = {409-410}, doi = {10.1155/S0161171298000568}, zbl = {0895.54017}, language = {en}, url = {http://dml.mathdoc.fr/item/01140287} }
Vallin, Robert W. A subset of metric preserving functions.. International Journal of Mathematics and Mathematical Sciences, Tome 21 (1998) pp. 409-410. doi : 10.1155/S0161171298000568. http://gdmltest.u-ga.fr/item/01140287/