International Union of Official Travel Organisations European Travel Commission, World Tourism Organization, & University of Luton. (2003). Evaluating NTO marketing activities: A joint ... (UK). World Tourism Organization.
Παραπομπή σε μορφή Chicago (17η εκδ.)International Union of Official Travel Organisations European Travel Commission, World Tourism Organization, και University of Luton. Evaluating NTO Marketing Activities: A Joint ... (UK). Madrid, Spain: World Tourism Organization, 2003.
Παραπομπή σε μορφή MLA (9th εκδ.)International Union of Official Travel Organisations European Travel Commission, et al. Evaluating NTO Marketing Activities: A Joint ... (UK). World Tourism Organization, 2003.
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