@article{DBLP:journals/cma/ZhangLJW06,
  author    = {Xiaoying Zhang and
               Xiaoyue Li and
               Daqing Jiang and
               Ke Wang},
  title     = {Multiplicity Positive Solutions to Periodic Problems for
               First-Order Impulsive Differential Equations},
  journal   = {Computers {\&} Mathematics with Applications},
  volume    = {52},
  number    = {6-7},
  year      = {2006},
  pages     = {953-966},
  ee        = {http://dx.doi.org/10.1016/j.camwa.2006.04.019},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}