Shadis, Miriam (2010). Berenguela of Castile (1180–1246) and Political Women in the High Middle Ages. Palgrave Macmillan. ISBN 978-0-312-23473-7.
↑ Chronica Albrici Monachi Trium Fontium, "Henricum qui iuvenis obiit et quinque sorores, prima Berengaria… secunda Urraca, tertia regina Francie, quarta Alienor, quinta Constantia monialis"
1 2 3 4 Martínez Díez , Gonzalo (2007). Alfonso VIII, king of Castile and Toledo (1158-1214) . Gijón: Ediciones Trea, SL ISBN 978-84-9704-327-4, p. 52
