Srivastava, K., Sinha, P., Sharma, R. and Gupta, U. (2017) “A comparative study of the effect of drotaverine hydrochloride with hyoscine butylbromide in first stage of labor”, International Journal of Basic & Clinical Pharmacology, 4(3), pp. 488–491. doi: 10.18203/2319-2003.ijbcp20150025.