@article{JNSA_2017_10_3_a4,
     author = {Ding, Yanhui and Chen, Min},
     title = {Positive and negative solutions of impulsive functional differential equations },
     journal = {Journal of nonlinear sciences and its applications},
     pages = {922-928},
     publisher = {mathdoc},
     volume = {10},
     number = {3},
     year = {2017},
     doi = {10.22436/jnsa.010.03.05},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.22436/jnsa.010.03.05/}
}