Roadle's illustrated Encyclopedia of Herbs
Claire Kowalchik & William Hylton (1987) Pennsylvania: Rodale Press

Growing & Using the Healing Herbs
Gaea & Snado Weiss (1985). New York: Wings Books The Healing Herbs.
Michael Castleman (1991). Pennsylvania: Rodale Press

Identifying and Harvesting Edible and Medicinal Plants in Wild
(and not so wild) Places
Steve Brill & Evelyn Dean (1994). New York: Hearst A Modern Herbal:
Volumes 1 & 2. Mrs. M. Grieve (1971). New York: Dover Publishing

The Herbal Connection
Herb Growing & Marketing Network (1996). Vol 5, No.2: Silver Spring, PA 17575

Spontaneous Healing
Andrew Weil, M.D. (1995). New York: Alfred Knopf, Inc.

Eastern/Central Medicinal Plants. Peterson Field Guides
Steven Foster & James Duke. 1990. New York: Houghton Mifflin Publishing Co.