Salem, M. M., Abd-El Aziz, M. S., Wahba, S. S., Mahmoud, S. F., Sery, M. M. (2018). 'Analgesic Efficacy and Outcome of Lumber Epidural Analgesia versus ultrasound guided Trasversus Abdominis Plane block In Laparoscopic Sleeve Gastrectomy', The Egyptian Journal of Hospital Medicine, 72(6), pp. 4753-4760. doi: 10.21608/ejhm.2018.9852