APA (7th ed.) Citation

Foster, S. (1990). A field guide to medicinal plants: Eastern and Central North America. Houghton Mifflin Co.

Chicago Style (17th ed.) Citation

Foster, Steven. A Field Guide to Medicinal Plants: Eastern and Central North America. Boston: Houghton Mifflin Co, 1990.

MLA (9th ed.) Citation

Foster, Steven. A Field Guide to Medicinal Plants: Eastern and Central North America. Houghton Mifflin Co, 1990.