@article{1206135653,
author = {Graef, John R. and Spikes, Paul W.},
title = {Nonoscillation criteria for differential equations of the second order},
journal = {Hiroshima Math. J.},
volume = {7},
number = {3},
year = {1977},
pages = { 675-681},
language = {en},
url = {http://dml.mathdoc.fr/item/1206135653}
}
Graef, John R.; Spikes, Paul W. Nonoscillation criteria for differential equations of the second order. Hiroshima Math. J., Tome 7 (1977) no. 3, pp. 675-681. http://gdmltest.u-ga.fr/item/1206135653/