APA (7th ed.) Citation

Williams, P. D. (2013). Security studies an introduction (2nd ed.). Routledge.

Chicago Style (17th ed.) Citation

Williams, Paul D. Security Studies an Introduction. 2nd ed. London [etc.]: Routledge, 2013.

MLA (9th ed.) Citation

Williams, Paul D. Security Studies an Introduction. 2nd ed. Routledge, 2013.