APA (7th ed.) Citation

Norwich, J. J. (1991). Byzantium: The apogee. Penguin Books.

Chicago Style (17th ed.) Citation

Norwich, John Julius. Byzantium: The Apogee. London: Penguin Books, 1991.

MLA (8th ed.) Citation

Norwich, John Julius. Byzantium: The Apogee. Penguin Books, 1991.

Warning: These citations may not always be 100% accurate.