توثيق جمعية علم النفس الأمريكية APA (الطبعة السابعة)

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.

توثيق أسلوب شيكاغو (الطبعة السابعة عشر)

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.

توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)

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.