APA (7th ed.) Citation

Pirenne, H., Pirenne, J., Vercauteren, F., & Miall, B. (1939). Mohammed and Charlemagne. Allen & Unwin.

Chicago Style (17th ed.) Citation

Pirenne, Henri, Jacques Pirenne, Fernand Vercauteren, and Bernard Miall. Mohammed and Charlemagne. London: Allen & Unwin, 1939.

MLA (9th ed.) Citation

Pirenne, Henri, et al. Mohammed and Charlemagne. Allen & Unwin, 1939.