APA (7th ed.) Citation

3G E-Learning LLC, USA. (2018). Travel services: Intermediate (2nd edition.). 3G E-Learning LLC.

Chicago Style (17th ed.) Citation

3G E-Learning LLC, USA. Travel Services: Intermediate. 2nd edition. New York, NY: 3G E-Learning LLC, 2018.

MLA (9th ed.) Citation

3G E-Learning LLC, USA. Travel Services: Intermediate. 2nd edition. 3G E-Learning LLC, 2018.