Singh, Sanjay, M. K. Giri, Mayurika Singh, and Navin Kumar Giri. 2019. “A Clinical Comparative Study of Intraperitoneal Instillation of Ropivacaine Alone or Ropivacaine With Nalbuphine for Postoperative Analgesia in Laparoscopic Cholecystectomy”. Anaesthesia, Pain & Intensive Care, January, 335-39. https://apicareonline.com/index.php/APIC/article/view/135.