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2. CLIA, 2014. The Cruise Industry, Contribution of Cruise Tourism to the Economies of Europe 2014 Edition. Brussels.
3. DATELINE, 2001. Deliverable 2, Final Survey Design for a European Travel Survey on Long-distance Mobility.
4. DATELINE, 2003 (1). Deliverable 5, Final Report on Data Collection.
5. DATELINE, 2003 (2). Deliverable 10b, Weighting and Grossing up Report.