APA (7th ed.) Zitazioa
Urwellen, R. H. (2009). Oil spill costs and impacts. Nova Science Publishers, Inc..
Chicago Style (17th ed.) Zitazioa
Urwellen, Robert H. Oil Spill Costs and Impacts. New York: Nova Science Publishers, Inc., 2009.
MLA (9th ed.) Zitazioa
Urwellen, Robert H. Oil Spill Costs and Impacts. Nova Science Publishers, Inc., 2009.
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