N. A. Samat and  D. F. Percy,  Numerical Analysis of the SIR-SI Differential Equations with Application to Dengue Disease Mapping in Kuala Lumpur, Malaysia.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    July 2013, vol. 79(7). 1085 - 1094
    [viewed 23 February 2020]. Available from: https://publications.waset.org/pdf/16320.