1. Chen, LJ, Chen, FD: Extinction in a discrete Lotka-Volterra competitive system with the effect of toxic substances and feedback controls. Int. J. Biomath. 8(1), Article ID 1550012 (2015)
2. Maynard Smith, J: Models in Ecology, p. 146. Cambridge University Press, London (1974)
3. Chattopadhyay, J: Effect of toxic substances on a two species competitive system. Ecol. Model. 84, 287-289 (1996)
4. Li, Z, Chen, FD: Extinction in two dimensional nonautonomous Lotka-Volterra systems with the effect of toxic substances. Appl. Math. Comput. 182, 684-690 (2006)
5. Murry, JD: Mathematical Biology. Springer, New York (1989)