Hoff and Overgaard & World Tourism Organization. (1992). Tourism master plan for the Philippines. World Tourism Organization.
Chicago-viite (17. p.)Hoff and Overgaard ja World Tourism Organization. Tourism Master Plan for the Philippines. [Madridn]: World Tourism Organization, 1992.
MLA-viite (9. p.)Hoff and Overgaard ja World Tourism Organization. Tourism Master Plan for the Philippines. World Tourism Organization, 1992.
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