A Control Mathematical Model for the Survival of a Biological Species Affected by Two Toxicants, One Emitted from External Sources as well as Formed by its Precursors and the Other Produced by Species itself. J. Int. Acad. Phys. Sci. [Internet]. 2015 Mar. 15 [cited 2026 Oct. 23];19(1):9-33. Available from: http://www.iaps.org.in/journal/index.php/journaliaps/article/view/341