Mill, R. C., & Morrison, A. M. (1992). The tourism system: An introductory text (2nd ed.). Prentice-Hall.
Lua i Stíl Chicago (17ú heag.)Mill, Robert Christie, agus Alastair M. Morrison. The Tourism System: An Introductory Text. 2nd ed. Englewood Cliffs, N.J: Prentice-Hall, 1992.
Lua MLA (9ú heag.)Mill, Robert Christie, agus Alastair M. Morrison. The Tourism System: An Introductory Text. 2nd ed. Prentice-Hall, 1992.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.