WCSP (2015). World Checklist of Selected Plant Families. Facilitated by the Royal Botanic Gardens, Kew. Last accessed on Last accessed on Sunday, 23 June, 2019.
Image #00 (cropped) & #01 (original) used with the permission of the National Museum of Natural History, Smithsonian Institution, 10th and Constitution Ave. N.W., Washington, DC 20560-0193. Last accessed on Monday, 15 July, 2019.