APA引用形式

(2011). Keeping track of our changing environment from Rio to Rio + 20 (1992-2012). UNEP.

シカゴスタイル引用形

Keeping Track of Our Changing Environment from Rio to Rio + 20 (1992-2012). Nairobi: UNEP, 2011.

MLA引用形式

Keeping Track of Our Changing Environment from Rio to Rio + 20 (1992-2012). UNEP, 2011.