International Union of Official Travel Organisations. (1971). Methodology for annual and medium-term forecasts. International Union of Official Travel Organisations.
Цитирование в стиле Чикаго (17-е изд.)International Union of Official Travel Organisations. Methodology for Annual and Medium-term Forecasts. Geneva: International Union of Official Travel Organisations, 1971.
Цитирование MLA (9-е изд.)International Union of Official Travel Organisations. Methodology for Annual and Medium-term Forecasts. International Union of Official Travel Organisations, 1971.
Предупреждение: эти цитированмия не могут быть всегда правильны на 100%.