APA (7th ed.) Citation

Butler, M., & De Lavalle, M. C. (2003). Worldwide cruise ship activity. World Tourism Organization.

Chicago Style (17th ed.) Citation

Butler, Manuel, and Manuel Carlier De Lavalle. Worldwide Cruise Ship Activity. Madrid, Spain: World Tourism Organization, 2003.

MLA (9th ed.) Citation

Butler, Manuel, and Manuel Carlier De Lavalle. Worldwide Cruise Ship Activity. World Tourism Organization, 2003.