Cita APA (7th ed.)

Morris, R. B., & Irwin, G. W. (1970). Harper encyclopedia of the modern world: A concise reference history from 1760 to the present. Harper & Row.

Cita Chicago (17th ed.)

Morris, Richard Brandon, i Graham W. Irwin. Harper Encyclopedia of the Modern World: A Concise Reference History from 1760 to the Present. New York: Harper & Row, 1970.

Cita MLA (9th ed.)

Morris, Richard Brandon, i Graham W. Irwin. Harper Encyclopedia of the Modern World: A Concise Reference History from 1760 to the Present. Harper & Row, 1970.