European Travel Commission. (1969). Freedom to travel: An economic study of the advantages of the development of international tourism without restrictions. European Travel Commission.
Citazione stile Chigago Style (17a edizione)European Travel Commission. Freedom to Travel: An Economic Study of the Advantages of the Development of International Tourism Without Restrictions. Dublin, Ireland: European Travel Commission, 1969.
Citatione MLA (8a ed.)European Travel Commission. Freedom to Travel: An Economic Study of the Advantages of the Development of International Tourism Without Restrictions. European Travel Commission, 1969.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.