APA Style

GUINNESS, P., WALPOLE, B. (2016). Environmental systems and societies for the IB Diploma second edition (ORG) (2nd Edition). Cambridge-UK-New York: Cambridge UP.

MLA Style

GUINNESS, Paul., WALPOLE, Brenda. "Environmental systems and societies for the IB Diploma second edition (ORG)". 2nd Edition Cambridge-UK-New York: Cambridge UP, 2016. Text.