Books, Brochures, and Chapters>Book:  Marx, Karl and Engels , Friedrich (1975-06-01), Karl Marx, Frederick Engels, Intl Pub, Retrieved on 2014-01-22

Source Material [books.google.com]

Books, Brochures, and Chapters>Book:  Friedrich, Marx, Engels (1888), The Communist Manifesto, Retrieved on -0001-11-30

Source Material [www.gutenberg.org]