Seward, W. H. 1., & Cass, L. (1850). Speeches of Hon. William H. Seward, and Hon. Lewis Cass on the subject of slavery: Delivered in the Senate of the United States, March 1850. New York: Stringer & Townsend.

Seward, William H. 1801-1872., and Lewis Cass. Speeches of Hon. William H. Seward, and Hon. Lewis Cass On the Subject of Slavery: Delivered in the Senate of the United States, March 1850. New York: Stringer & Townsend, 1850.

Seward, William H. 1801-1872., and Lewis Cass. Speeches of Hon. William H. Seward, and Hon. Lewis Cass On the Subject of Slavery: Delivered in the Senate of the United States, March 1850. New York: Stringer & Townsend, 1850.