Suthinee Boonananwong, Boonsong Kongkathip, and Ngampong Kongkathip. 2008. “Synthesis and Biological Evaluation of 3,16,20-Polyoxygenated Steroids of Marine Origin and Their Analogs”. Agriculture and Natural Resources 42 (3). Bangkok, Thailand:531-42. https://li01.tci-thaijo.org/index.php/anres/article/view/244481.