APA (7th ed.) Citation

Keen, M. H. (1969). The Pelican history of medieval Europe. Penguin.

Chicago Style (17th ed.) Citation

Keen, Maurice Hugh. The Pelican History of Medieval Europe. Harmondsworth, Eng.: Penguin, 1969.

MLA (9th ed.) Citation

Keen, Maurice Hugh. The Pelican History of Medieval Europe. Penguin, 1969.

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