APA (7th ed.) Zitazioa
Spellenberg, R., Earle, C. J., Nelson, G., More, D., & Hughes, A. K. (2014). Trees of Western North America. Princeton University Press.
Chicago Style (17th ed.) Zitazioa
Spellenberg, Richard, Christopher J. Earle, Gil Nelson, David More, eta Amy K. Hughes. Trees of Western North America. Princeton, New Jersey: Princeton University Press, 2014.
MLA (9th ed.) Zitazioa
Spellenberg, Richard, et al. Trees of Western North America. Princeton University Press, 2014.
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