Singh, R.B., Singh, D., Mishra, P.K., Kumar, M. and Kumar, V. 2017. Epidural ropivacaine combined with fentanyl or in combination with clonidine in infraumblical surgeries: a comparative study. International Journal of Research in Medical Sciences. 3, 10 (Jan. 2017), 2740–2744. DOI:https://doi.org/10.18203/2320-6012.ijrms20150824.