GOPAL V V. (2005). CRM IN TRAVEL AND TOURISM: CONCEPTS AND CASES. ICFAI BOOKS.
Lua i Stíl Chicago (17ú heag.)GOPAL V V. CRM IN TRAVEL AND TOURISM: CONCEPTS AND CASES. HYDERABAD: ICFAI BOOKS, 2005.
Lua MLA (9ú heag.)GOPAL V V. CRM IN TRAVEL AND TOURISM: CONCEPTS AND CASES. ICFAI BOOKS, 2005.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.