Black Freedom Struggle in the United States:

A Century of Negro Migration

Monograph by Carter G. Woodson, a Black historian, author, Newsist, and founder of the Association for the Study of African American Life and History, that traces the history of African American migration to northern U.S. states., 1918

African slave-trade.

Liberia, purchase of Territory in, by American Colonization Society, for suppression of African slave trade, 1844

African colonization — Slave trade — Commerce. Report of Mr. Kennedy, of Maryland, from the Committee on Commerce of the House of Representatives of the United States, on the memorial of the Friends of African Colonization, assembled in convention in the City of Washington, May, 1842. To which is appended, a collection of the most interesting papers on the subject of African colonization, and the commerce, etc., of Western Africa, together with all the diplomatic correspondence between the United States and Great Britain, on the subject of the African slave trade.

Colonization of free men in Africa, diplomatic correspondence with Great Britain on slave trade and commerce, 1843