APA (7th ed.) Zitazioa
Williams, D., & Butler, B. (2010). The Tallgrass Prairie Center guide to seed and seedling identification in the Upper Midwest. Published for the Tallgrass Prairie Center by the University of Iowa Press.
Chicago Style (17th ed.) Zitazioa
Williams, Dave, eta Brent Butler. The Tallgrass Prairie Center Guide to Seed and Seedling Identification in the Upper Midwest. Iowa City: Published for the Tallgrass Prairie Center by the University of Iowa Press, 2010.
MLA (9th ed.) Zitazioa
Williams, Dave, eta Brent Butler. The Tallgrass Prairie Center Guide to Seed and Seedling Identification in the Upper Midwest. Published for the Tallgrass Prairie Center by the University of Iowa Press, 2010.
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