World Tourism Organization. (1981). Organization and operation of the statistics service within the National Tourism Administration: Basic guidelines. The Organization.
Chicago-Zitierstil (17. Ausg.)World Tourism Organization. Organization and Operation of the Statistics Service Within the National Tourism Administration: Basic Guidelines. Madrid: The Organization, 1981.
MLA-Zitierstil (9. Ausg.)World Tourism Organization. Organization and Operation of the Statistics Service Within the National Tourism Administration: Basic Guidelines. The Organization, 1981.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.