Kumar, R., Sachan, P., Singh, S.K., Gupta, A.K. and Mohan, L. 2019. A prospective observational study on efficacy of black acetic acid combination peel in patients of facial nodulocystic acne. International Journal of Research in Dermatology. 5, 4 (Oct. 2019), 673–677. DOI:https://doi.org/10.18203/issn.2455-4529.IntJResDermatol20194544.