Helene J. Jordan. (1992). How a Seed Grows (Let's-Read-and-Find-Out Science 1) (Revised ed.). HarperCollins.
Čikaški stil citiranja (17. izdanje)Helene J. Jordan. How a Seed Grows (Let's-Read-and-Find-Out Science 1). Revised ed. HarperCollins, 1992.
MLA način citiranja (9. izdanje)Helene J. Jordan. How a Seed Grows (Let's-Read-and-Find-Out Science 1). Revised ed. HarperCollins, 1992.
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