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Lua i Stíl Chicago (17ú heag.)Wulf, Luc de, agus José B. Sokol. Customs Modernization Handbook. Washington, DC: World Bank, 2005.
Lua MLA (9ú heag.)Wulf, Luc de, agus José B. Sokol. Customs Modernization Handbook. World Bank, 2005.
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