Sivakumar, R., et al. “Investigation on Eco-Friendly Natural Dyes: Chemistry, Dyeing and Antimicrobial Properties of Helichrysum Bracteatum”. Asian Journal of Chemistry, vol. 21, no. 8, Mar. 2010, pp. 5960-6, https://asianpubs.org/index.php/ajchem/article/view/12276.