Abbas, S. A., M. Bajwa, and Z. Ahmed. “Etiologies of Unilateral Pleural Effusion and Complications of Intercostal Drains”. Pakistan Journal of Chest Medicine, vol. 23, no. 1, June 2017, pp. 08-14, https://www.pjcm.net/index.php/pjcm/article/view/433.