Al-Ani, M. S., and D. M. Al-Ani. “Review Study on Sciencedirect Library Based on Coronavirus Covid-19: Covid-19 Study”. UHD Journal of Science and Technology, vol. 4, no. 2, Aug. 2020, pp. 46-55, doi:10.21928/uhdjst.v4n2y2020.pp46-55.