Aldeeb, G. A., and S. M. El-Demerdash. “Head nurses’ Transformational Leadership, Collaboration and Its Relation to Staff nurses’Work Engagement”. International Journal of Nursing Didactics, vol. 6, no. 7, July 2016, pp. 30-39, https://www.nursingdidactics.com/index.php/ijnd/article/view/1807.