Elmugabil, A., D. A. Rayis, M. A. Ahmed, I. Adam, and G. I. Gasim. “O Blood Group As Risk Factor for Preeclampsia Among Sudanese Women”. Open Access Macedonian Journal of Medical Sciences, vol. 4, no. 4, Sept. 2016, pp. 603-6, doi:10.3889/oamjms.2016.108.