Paul Guinness; Brenda Walpole. (2012). Environmental Systems and Societies for the IB Diploma. CAMBRIDGE UNIVERSITY PRESS.
Chicago-referens (17:e uppl.)Paul Guinness; Brenda Walpole. Environmental Systems and Societies for the IB Diploma. CAMBRIDGE UNIVERSITY PRESS, 2012.
MLA-referens (9:e uppl.)Paul Guinness; Brenda Walpole. Environmental Systems and Societies for the IB Diploma. CAMBRIDGE UNIVERSITY PRESS, 2012.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.