Esmeal, Maha Esmeal Ahmed, et al. “Evaluation of First Trimester Miscarriage Among Sudanese Woman in Khartoum State Using Ultrasonography”. International Journal of Innovative Research in Medical Science, vol. 4, no. 12, Dec. 2019, p. 647 to 651, doi:10.23958/ijirms/vol04-i12/784.