Tham khảo Otto IV của Thánh chế La Mã

  • Abulafia, David, The New Cambridge Medieval History, Vol. V: c. 1198 – c. 1300, Cambridge University Press, 1999
  • Bryce, James, The Holy Roman Empire, 1913
  • Comyn, Robert. History of the Western Empire, from its Restoration by Charlemagne to the Accession of Charles V, Vol. I. 1851
  • Dunham, S. A., A History of the Germanic Empire, Vol. I, 1835
  • Huffman, Joseph Patrick (2000). “Richard the Lionheart and Otto IV: Itinerant Kingship and the City of Cologne”. The Social Politics of Medieval Diplomacy: Anglo-German Relations (1066–1307). University of Michigan Press. tr. 133–77.
  • Keefe, Thomas K. (1983). Feudal Assessments and the Political Community Under Henry II and His Sons. University of California Press. ISBN 9780520045828.
  • McLynn, Frank (2007). Lionheart and Lackland: King Richard, King John and the Wars of Conquest. Vintage.
  • Murray, Alan (1994). “Richard the Lionheart, Otto of Brunswick and the Earldom of York: Northern England and the Angevin Succession, 1190–91”. Medieval Yorkshire. 23: 5–12.
  • Norgate, Kate (1887). England Under the Angevin Kings. Macmillan.

Tài liệu tham khảo

WikiPedia: Otto IV của Thánh chế La Mã https://archive.org/details/feudalassessment0000ke... https://archive.org/stream/englandunderange02norgu... https://commons.wikimedia.org/wiki/Category:Otto_I... https://portal.dnb.de/opac.htm?method=simpleSearch... https://www.deutsche-digitale-bibliothek.de/entity... http://opac.regesta-imperii.de/lang_de/suche.php?t... https://web.archive.org/web/20131014151815/http://... http://kulturerbe.niedersachsen.de/viewer/image/is...