The following sources were consulted in the preparation of the article “History’s 10 most influential illegitimate children.”
- Matilda of England, empress
- William I ‘The Conqueror’ (r. 1066-1087)
- Holy Great Prince Vladimir (Basil in Baptism), Equal of the Apostles, and Enlightener of Rus’
- Henry II of Trastámara (1366–1367, 1369–1379)
- Milan, Leonardo and the Sforza family
- Cesare Borgia, Duke of Valentinois
- Don John of Austria
- Federigo da Montefeltro, 1422-1482, Count of Urbino 1444, and Duke 1474
- Morny, Charles Auguste Louis Joseph, duc de (1811 – 1865)