K. GOWRI SHANKAR, et al. “Synergistic Efficacy of Three Plant Extracts, Bergeniaciliata, Acoruscalamus and Dioscoreabulbifera for Antimicrobial Activity”. International Journal of Pharma and Bio Sciences, vol. 7, no. 4, Dec. 2016, pp. 619-28, https://ijpbs.net/index.php/journal/article/view/5527.