Amerini, G. (2008). Maritime transport of goods and passengers 1997-2006. Statistics in focus: Transport.
Chicago-referens (17:e uppl.)Amerini, Giuliano. "Maritime Transport of Goods and Passengers 1997-2006." Statistics in Focus: Transport 2008.
MLA-referens (8:e uppl.)Amerini, Giuliano. "Maritime Transport of Goods and Passengers 1997-2006." Statistics in Focus: Transport, 2008.
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