@article{00770115, title = {Applications of the method of barriers. II: Some singularly perturbed problems.}, journal = {Georgian Mathematical Journal}, volume = {2}, year = {1995}, pages = {323-334}, doi = {10.1007/BF02261705}, zbl = {0833.34017}, language = {en}, url = {http://dml.mathdoc.fr/item/00770115} }
Sushko, V.G.; Rozov, N.Kh. Applications of the method of barriers. II: Some singularly perturbed problems.. Georgian Mathematical Journal, Tome 2 (1995) pp. 323-334. doi : 10.1007/BF02261705. http://gdmltest.u-ga.fr/item/00770115/