Paul Guinness; Brenda Walpole. (2012). Environmental Systems and Societies for the IB Diploma. CAMBRIDGE UNIVERSITY PRESS.
Čikaški stil citiranja (17. izdanje)Paul Guinness; Brenda Walpole. Environmental Systems and Societies for the IB Diploma. CAMBRIDGE UNIVERSITY PRESS, 2012.
MLA način citiranja (9. izdanje)Paul Guinness; Brenda Walpole. Environmental Systems and Societies for the IB Diploma. CAMBRIDGE UNIVERSITY PRESS, 2012.
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