GILBERTSON, D. (1989). Practical Ecology For Geography And Biology. Croom Helm.
Čikaški stil citiranja (17. izdanje)GILBERTSON, DD. Practical Ecology For Geography And Biology. Croom Helm, 1989.
MLA način citiranja (8. izdanje)GILBERTSON, DD. Practical Ecology For Geography And Biology. Croom Helm, 1989.
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