APA (7th ed.) Citation

Orwell, G., Perkins-Valdez, D., & Newman, S. 1984 (75th Anniversary Edition.).

Chicago Style (17th ed.) Citation

Orwell, George, Dolen Perkins-Valdez, and Sandra Newman. 1984. 75th Anniversary Edition. New York.

MLA (9th ed.) Citation

Orwell, George, et al. 1984. 75th Anniversary Edition.