APA (7th ed.) Citation

Thomas, H. (1981). An unfinished history of the world (Rev. ed.). Pan.

Chicago Style (17th ed.) Citation

Thomas, Hugh. An Unfinished History of the World. Rev. ed. London: Pan, 1981.

MLA (8th ed.) Citation

Thomas, Hugh. An Unfinished History of the World. Rev. ed. Pan, 1981.