Misra, O.P., and Raveendra Babu.A. “A Model for the Effect of Toxicant on a Three Species Food-Chain System With ‘Food-Limited’ Growth of Prey Population”. Global Journal of Mathematical Analysis, vol. 2, no. 3, July 2014, pp. 120-45, https://doi.org/10.14419/gjma.v2i3.2990.