@article{03615100, title = {Behavior of second order nonlinear differential equations.}, journal = {International Journal of Mathematics and Mathematical Sciences}, volume = {1}, year = {1978}, pages = {1-12}, doi = {10.1155/S0161171278000010}, zbl = {0396.34028}, language = {en}, url = {http://dml.mathdoc.fr/item/03615100} }
Ling, Rina. Behavior of second order nonlinear differential equations.. International Journal of Mathematics and Mathematical Sciences, Tome 1 (1978) pp. 1-12. doi : 10.1155/S0161171278000010. http://gdmltest.u-ga.fr/item/03615100/