APA (7th ed.) Citation

Procopius, Atwater, R., & Boak, A. E. R. (1994). Secret history. University of Michigan Press.

Chicago Style (17th ed.) Citation

Procopius, Richard Atwater, and Arthur E. R. Boak. Secret History. Ann Arbor: University of Michigan Press, 1994.

MLA (9th ed.) Citation

Procopius, et al. Secret History. University of Michigan Press, 1994.