The Shaman's Apprentice by Lynne Cherry and Mark J. Plotkin
Medicinal Plants of the Heartland by Connie Kaye and Neil Billington
Potions, Poisons, and Panaceas by David Brussell
Origin and Early Diversification of Land Plants by P. Kenrick & P.R. Crane
Ethnobotanical Leaflets: Vol. 1998
, Article 7.
Available at: http://opensiuc.lib.siu.edu/ebl/vol1998/iss3/7