Khalil, M., Said, M., Osman, H., Ahmed, B., Ahmed, D., Younis, N., Maher, B., Osama, M., & Ashmawy, M. (2019). Fractional order models of infectious diseases: a review. SPC Journal of Environmental Sciences, 1(1), 1-11. https://doi.org/10.14419/jes.v1i1.19436