Shrestha, C., Sharma, K., & Shrestha, R. (2007). Comparative study of epidural administration of 10 ml of 0.1% bupivacaine with 2 mg butorphanol and 10 ml of 0.25% plain bupivacaine for analgesia during labor. Journal of Nepal Medical Association, 46(165). https://doi.org/10.31729/jnma.409