Tài liệu tham khảo WikiPedia: Chi_Ba_đậu http://www.botanical.com/botanical/mgmh/c/croto118... http://www.yourdictionary.com/cascarilla http://www.botany.wisc.edu/croton/ http://www.ars-grin.gov/cgi-bin/npgs/html/splist.p... http://apps.kew.org/wcsp/synonomy.do?name_id=49179 http://www.theplantlist.org/browse/A/Euphorbiaceae... https://web.archive.org/web/20090120130955/http://... https://web.archive.org/web/20100820205646/http://... https://commons.wikimedia.org/wiki/Category:Croton... https://species.wikimedia.org/wiki/Croton?uselang=...
