Cita APA

Gilbert,Martin. (1999). Challenge to civilization: A history of the 20th century 1952-1999. Harper Collins.

Citación estilo Chicago

Gilbert,Martin. Challenge to Civilization: A History of the 20th Century 1952-1999. London: Harper Collins, 1999.

Cita MLA

Gilbert,Martin. Challenge to Civilization: A History of the 20th Century 1952-1999. Harper Collins, 1999.