APA (7th ed.) Citation

Campbell, G., & Evans, I. O. (1974). The book of flags (7th ed.). Oxford University Press.

Chicago Style (17th ed.) Citation

Campbell, Gordon, and I. O. Evans. The Book of Flags. 7th ed. London: Oxford University Press, 1974.

MLA (9th ed.) Citation

Campbell, Gordon, and I. O. Evans. The Book of Flags. 7th ed. Oxford University Press, 1974.