KREBS, C. J. (1989). Ecological Methodology Charles J. Krebs. Harper & Row.
Lua i Stíl Chicago (17ú heag.)KREBS, Charles J. Ecological Methodology Charles J. Krebs. Harper & Row, 1989.
Lua MLA (8ú heag.)KREBS, Charles J. Ecological Methodology Charles J. Krebs. Harper & Row, 1989.
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