Zhouhong Li and Jiming Yang, Multiple Positive Periodic Solutions to a Periodic Predator-Prey-Chain Model with Harvesting Terms. journal = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology. August 2011, vol. 56(8). 1292 - 1297 [viewed 20 September 2024]. Available from: https://publications.waset.org/pdf/1330.