Madhala, K.; Kumar, G. N.; Padma, M. N.; Parasa, S. K. Evaluation of Analgesia by Epidural Fentanyl and MgSO4 With Fentanyl for Postoperative Analgesia in Patients of Lower Abdominal Surgeries: A Comparative Study. Int. J. of Health Sci. 2022, 6, 10390-10399.