Roll-Hansen, N. Sources of Johannsen's Genotype Theory: Nils Roll-Hansen. Conference A Cultural History of Heredity III : 19th and early 20th centuries.(2005).
Čikaški stil citiranja (17. izdanje)Roll-Hansen, Nils. "Sources of Johannsen's Genotype Theory: Nils Roll-Hansen." Conference A Cultural History of Heredity III : 19th and Early 20th Centuries.(2005) .
MLA način citiranja (8. izdanje)Roll-Hansen, Nils. "Sources of Johannsen's Genotype Theory: Nils Roll-Hansen." Conference A Cultural History of Heredity III : 19th and Early 20th Centuries.(2005), .
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