MECW Volume 18, p. 40; Written by Frederick Engles in July and the first 10 days of August 1857; First published in the New American Cyclopaedia — Vol. I, 1858;…Link [Архівовано 18 жовтня 2010 у Wayback Machine.]
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MECW Volume 18, p. 40; Written by Frederick Engles in July and the first 10 days of August 1857; First published in the New American Cyclopaedia — Vol. I, 1858;…Link [Архівовано 18 жовтня 2010 у Wayback Machine.]
