Harold L. Vogel. (2012). Travel Industry Economics (2.). Cambridge University Press.
Lua i Stíl Chicago (17ú heag.)Harold L. Vogel. Travel Industry Economics. 2. Cambridge University Press, 2012.
Lua MLA (8ú heag.)Harold L. Vogel. Travel Industry Economics. 2. Cambridge University Press, 2012.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.