The New Cambridge medieval history.

MLA

Allmand, Christopher, et al. The New Cambridge Medieval History. Cambridge [England]: Cambridge University Press, 1995.

APA

Allmand, C., Fouracre, P., Luscombe, D., McKitterick, R., & Reuter, T. (1995). The New Cambridge medieval history. Cambridge [England]: Cambridge University Press.

Chicago

Allmand, Christopher ed., Paul Fouracre ed., David Luscombe ed., Rosamond McKitterick ed., and Timothy Reuter ed. The New Cambridge Medieval History. Cambridge [England]: Cambridge University Press, 1995.