Singapore Tourist Promotion Board. Research Dept. (1976). Pleasure/vacation visitors from the U.S.A. to Singapore with special reference to visitors on group tours, 1972-1974. Singapore Tourist Promotion Board.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)Singapore Tourist Promotion Board. Research Dept. Pleasure/vacation Visitors from the U.S.A. to Singapore with Special Reference to Visitors on Group Tours, 1972-1974. Singapore: Singapore Tourist Promotion Board, 1976.
Trích dẫn kiểu MLA (xuất bản lần thứ 8)Singapore Tourist Promotion Board. Research Dept. Pleasure/vacation Visitors from the U.S.A. to Singapore with Special Reference to Visitors on Group Tours, 1972-1974. Singapore Tourist Promotion Board, 1976.
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