Alzahrani, Faisal, Saeed Shaikh, and Muzaheed Rasheed. 2018. “Frequency of ABO-Rhesus Blood Groups in the Western Region of Saudi Arabia”. Journal of King Abdulaziz University - Medical Sciences 25 (1), 9-13. http://jkaumedsci.org.sa/index.php/jkaumedsci/article/view/548.