APA (7th ed.) Zitazioa
Shull, G. H. (1909). Bursa bursa-pastoris and bursa heegeri: Biotypes and Hybrids.
Chicago Style (17th ed.) Zitazioa
Shull, George Harrison. Bursa Bursa-pastoris and Bursa Heegeri: Biotypes and Hybrids. Washington, 1909.
MLA (9th ed.) Zitazioa
Shull, George Harrison. Bursa Bursa-pastoris and Bursa Heegeri: Biotypes and Hybrids. 1909.
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