Ultrasound-guided Erector Spinae Plane Block versus Oblique Subcostal Transversus Abdominis Plane Block for Postoperative Analgesia in Laparoscopic Cholecystectomy: A Prospective Observational Study - Wasim Mohammad Bhat; Suhaila Johar; Mariyah Riyaz; Masrat Jan; Hina Khurshid; Rohey Jan; Shazia Bashir; Nazir Ahmad Parray (JOURNAL OF CLINICAL AND DIAGNOSTIC RESEARCH, 2026)