Cita APA (7th ed.)
ebrary, Inc, Brown, J. M., Louis, W. R., & Low, A. M. (1999). The twentieth century. Oxford University Press.
Cita Chicago (17th ed.)
ebrary, Inc, Judith M. Brown, William Roger Louis, i Alaine M. Low. The Twentieth Century. Oxford: Oxford University Press, 1999.
Cita MLA (9th ed.)
ebrary, Inc, et al. The Twentieth Century. Oxford University Press, 1999.
Atenció: Aquestes cites poden no estar 100% correctes.