د. نضال حماد على حماد. “The Impact of Work Accidents on Productive Efficiency in Sudan Some Factories: (A Case Study of Operate in the White Nile State)”. White Nile Journal for Studies and Research, no. 18, Sept. 2021, pp. 9-27, https://journals.wnu.edu.sd/index.php/wnjsr/article/view/106.