@article{00645171, title = {Sturm's theorem for equations with delayed argument.}, journal = {Georgian Mathematical Journal}, volume = {1}, year = {1994}, pages = {267-276}, doi = {10.1007/BF02254675}, zbl = {0808.34073}, language = {en}, url = {http://dml.mathdoc.fr/item/00645171} }
Domoshnitsky, A. Sturm's theorem for equations with delayed argument.. Georgian Mathematical Journal, Tome 1 (1994) pp. 267-276. doi : 10.1007/BF02254675. http://gdmltest.u-ga.fr/item/00645171/