Riaz, Maj Azmat, et al. “ACUTE PAINFUL VASO-OCCLUSIVE SICKLE CELL CRISIS IN AN OPIOID TOLERANT PATIENT: Vaso-Occlusve Sickle Cell Crisis”. Pakistan Armed Forces Medical Journal, vol. 60, no. 2, June 2010, pp. 323-5, https://www.pafmj.org/PAFMJ/article/view/1827.