Paul Guinness; Brenda Walpole. (2012). Environmental Systems and Societies for the IB Diploma. CAMBRIDGE UNIVERSITY PRESS.
Chicago-viite (17. p.)Paul Guinness; Brenda Walpole. Environmental Systems and Societies for the IB Diploma. CAMBRIDGE UNIVERSITY PRESS, 2012.
MLA-viite (9. p.)Paul Guinness; Brenda Walpole. Environmental Systems and Societies for the IB Diploma. CAMBRIDGE UNIVERSITY PRESS, 2012.
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