@article{EJDE_2004__2004__a14,
     author = {Li,  Zhan and Shuai,  Zhisheng and Wang,  Ke},
     title = {Persistence and extinction of single population in a polluted environment},
     journal = {Electronic journal of differential equations},
     year = {2004},
     volume = {2004},
     zbl = {1084.92032},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2004__2004__a14/}
}