Mohsin, H. S., H. A. Ali, and F. J. Al-Tu’ma. “Assessment of Von Willebrand Factor/ADAMTS13 Ratio and Vitamin K Levels As Predictor Markers for Severity of COVID-19 Patients”. Journal of Contemporary Medical Sciences, vol. 7, no. 5, Oct. 2021, doi:10.22317/jcms.v7i5.1100.