World Tourism Organization. (1991). Tourism to the year 2000: Qualitative aspects Aafecting global growth: a discussion paper (executive summary). World Tourism Organization.
Παραπομπή σε μορφή Chicago (17η εκδ.)World Tourism Organization. Tourism to the Year 2000: Qualitative Aspects Aafecting Global Growth: A Discussion Paper (executive Summary). Madrid: World Tourism Organization, 1991.
Παραπομπή σε μορφή MLA (9th εκδ.)World Tourism Organization. Tourism to the Year 2000: Qualitative Aspects Aafecting Global Growth: A Discussion Paper (executive Summary). World Tourism Organization, 1991.
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