Naddoni, D.B., Balakundi, S.K. and Assainar, K.K. 2017. The effect of nitrous oxide (entonox) on labour. International Journal of Reproduction, Contraception, Obstetrics and Gynecology. 5, 3 (Feb. 2017), 835–839. DOI:https://doi.org/10.18203/2320-1770.ijrcog20160594.