APA
Hunter D., Vaughan S & Sommer J. (1994). Concepts And Principles Of International Environmental Law: An Introduction. Switzerland: UNEP.
Chicago
Hunter D, Vaughan S and Sommer J. 1994. Concepts And Principles Of International Environmental Law: An Introduction. Switzerland: UNEP.
Harvard
Hunter D., Vaughan S and Sommer J. (1994). Concepts And Principles Of International Environmental Law: An Introduction. Switzerland: UNEP.
MLA
Hunter D, Vaughan S and Sommer J. Concepts And Principles Of International Environmental Law: An Introduction. Switzerland: UNEP. 1994.