MILL, R. C. (1990). Tourism The International Business Robert Christie Mill. Prentice-Hall.
Lua i Stíl Chicago (17ú heag.)MILL, Robert Christie. Tourism The International Business Robert Christie Mill. Prentice-Hall, 1990.
Lua MLA (8ú heag.)MILL, Robert Christie. Tourism The International Business Robert Christie Mill. Prentice-Hall, 1990.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.