@article{GDZPPN002038536, title = {A generalization of Ostrowski' theorem on ultrametric inequalities.}, journal = {Aequationes mathematicae}, volume = {41}, year = {1991}, pages = {2-12}, zbl = {0723.12008}, url = {http://dml.mathdoc.fr/item/GDZPPN002038536} }
García-Roig, J.L. A generalization of Ostrowski' theorem on ultrametric inequalities.. Aequationes mathematicae, Tome 41 (1991) pp. 2-12. http://gdmltest.u-ga.fr/item/GDZPPN002038536/