@article{01791001, title = {Existence criteria for singular initial value problems with sign changing nonlinearities.}, journal = {Mathematical Problems in Engineering}, volume = {7}, year = {2001}, pages = {503-524}, doi = {10.1155/S1024123X01001752}, zbl = {1023.34001}, language = {en}, url = {http://dml.mathdoc.fr/item/01791001} }
Agarwal, Ravi P.; O'Regan, Donal; Lakshmikantham, V. Existence criteria for singular initial value problems with sign changing nonlinearities.. Mathematical Problems in Engineering, Tome 7 (2001) pp. 503-524. doi : 10.1155/S1024123X01001752. http://gdmltest.u-ga.fr/item/01791001/