- Moubach, Abraham (6)
- Picart, Bernard, 1673-1733 (6)
- Benezet, Anthony, 1713-1784 (4)
- Phillipps, Sir Thomas, 1792-1872 (3)
- Sharp, Granville, 1735-1813 (3)
- Alexander, of Tralles, approximately 525-approximately 605 (2)
- Clarkson, Thomas, 1760-1846 (2)
- Dickson, William (2)
- Godfrey, of Bouillon, approximately 1060-1100 (2)
- Great Britain. Parliament. House of Commons. Select Committee Appointed to Take the Examination of Witnesses Respecting the African Slave Trade (2)
- Hayton, Frère, approximately 1235-approximately 1314 (2)
- Henricus, de Hispania (2)
- Jordanus, canonicus osnaburgensis (2)
- Mandeville, Sir John (2)
- Pennsylvania Society for Promoting the Abolition of Slavery (2)
- Royal African Company (2)
- Theodericus, of Würzburg, active 1172 (2)
- da Verona, Jacopo, active 1335 (2)
- de Hese, Joannes (2)
- von Boldensele, Wilhelm, approximately 1285-approximately 1338 (2)