Bos, J. N. W. Maria I of Portugal. (页面存档备份,存于互联网档案馆) Published by J.N.W. Bos. Retrieved 15 December 2007. Dynes, Wayne. Palaces of Europe. London: Hamlyn
History of Portugal: From Lusitania to Empire, (Columbia University Press, 1972), 43. The title Count of Boulogne was held by King Afonso III of Portugal
IPPAR-Scala Publishers, 2002 (in Portuguese). Turner, J. - Grove Dictionary of Art - MacMillan Publishers Ltd., 1996; ISBN 1-884446-00-0 The Rough Guide