Randomized double blind controlled study of ropivacaine versus bupivacaine in combined spinal epidural anesthesia - Reddy, A Chandra Sekhar; Singh, Neha; Rao, Parnandi Bhaskar; Ramachandran, T. R.; George, Sagiev Koshy; Bhumika, Nateshan (Anaesthesia, Pain & Intensive Care, 2019)