[1]
د. علي خليفه الشيخ عبد الله and د. ياسر تاج السر محمد سند 2020. The Effect of Using Six Sigma Methodology Standards in Improving the Performance of the Internal Control System: A field study on government units in Algezira state. White Nile Journal for Studies and Research. 16 (Sep. 2020), 81–105.