Comparative Evaluation of Dexmedetomidine versus Fentanyl Added to Hyperbaric Levobupivacaine for Subarachnoid Block: Effects on Sensory-Motor Blockade and Analgesic Duration, P, Neethi T., C Prashanth Kumar, Uppangala Chaitra, Coelho Barbara, and Kumar Nayanatara Arun , Pharmacognosy Journal, September 2025, Volume 17, Issue 5, p.638-641, (2025)