%0 Journal Article
%T Positive Periodic Solutions of Nicholson-Type Delay Systems with Nonlinear Density-Dependent Mortality Terms
%A Wei Chen
%A Lijuan Wang
%J Abstract and Applied Analysis
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/843178
%U http://dx.doi.org/10.1155/2012/843178