Shadangi, B. K., R. Garg, and R. Pandey. “A Randomized, Placebo-Controlled, Doubleblind Study of the Analgesic Efficacy of Extraperitoneal Wound Instillation of Bupivacaine and Morphine in Abdominal Surgeries”. Anaesthesia, Pain & Intensive Care, Feb. 2019, pp. 169-73, https://apicareonline.com/index.php/APIC/article/view/511.