صلاح الدين, أحمد; 						عبد الهادي, محمد عثمان.
 Quality of Service.
<strong>Gezira Journal of Engineering and Applied Sciences</strong>, [S.l.], v. 11, n. 1, july 2018.
ISSN 1858-5698. Available at: &lt;<a href="http://journals.uofg.edu.sd/index.php/gjeas/article/view/519" target="_new">http://journals.uofg.edu.sd/index.php/gjeas/article/view/519</a>&gt;. Date accessed: 08 june 2026.