APA (7th ed.) Zitazioa
Krutch, J. W., & Landacre, P. (2009). The great chain of life (1st University of Iowa Press ed.). University of Iowa Press.
Chicago Style (17th ed.) Zitazioa
Krutch, Joseph Wood, eta Paul Landacre. The Great Chain of Life. 1st University of Iowa Press ed. Iowa City: University of Iowa Press, 2009.
MLA (9th ed.) Zitazioa
Krutch, Joseph Wood, eta Paul Landacre. The Great Chain of Life. 1st University of Iowa Press ed. University of Iowa Press, 2009.
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