Abid, Z., Yousuf, S., Qureshi, F., Rizvi, S. M., Ommid, M., Qureshi, F., & Masood, A. (2025). Comparison of butorphanol-drotaverine versus tramadol-drotaverine as labour analgesics: an observational comparative study. International Journal of Reproduction, Contraception, Obstetrics and Gynecology, 14(8), 2636–2642. https://doi.org/10.18203/2320-1770.ijrcog20252336