Confronted with internal strife, the commune of Bologna is the first Italian republic to turn to the rule of a podestà, Guido di Ranieri da Sasso (it ends in 1155).[14][15]
^Dutton, Kathryn (December 1, 2015). "Crusading and political culture under Geoffrey, count of Anjou and duke of Normandy, 1129–51". French History. 29 (4): 419–444. doi:10.1093/fh/crv014. ISSN0269-1191.
^Bombaci, Alessio (1959). "Summary report on the Italian Archaeological Mission in Afghanistan. Introduction to the Excavations at Ghazni". East and West. 10 (1/2): 3–22. ISSN0012-8376. JSTOR29754076.
^F.R.Hist.S., George R. Potter M. A. Ph d F. S. A. (December 15, 2009). "A note on the Devonshire papers at Ghatsworth House, Derbyshire". Journal of the Society of Archivists. 4 (2): 124–129. doi:10.1080/00379817009513947.
^Romanova, Anna; Yakushenkova, Olesia (August 2012). Ching Chan, Selina (ed.). "Comparative Analysis of the Image of the Stranger in Chinese and Russian Discourse". Proceedings of the 7th Annual Conference of the Asian Studies Association. Hong Kong Shue Yan University - The Contemporary China Research Center: 1160. ISBN978-988-18445-0-7. An example of Igor Svyatoslavich the Brave's life (1151-1202) is a good example of such types of relations with some nomadic tribes that lived close to the borders of Russian Kingdom.
^Inglis, Erik (September 1, 2015). "Remembering and Forgetting Suger at Saint-Denis, 1151–1534: An Abbot's Reputation between Memory and History". Gesta. 54 (2): 219–243. doi:10.1086/681955. ISSN0016-920X. S2CID163497330.
^Dalton, Paul (2007). "The Date of Geoffrey Gaimar's "Estoire Des Engleis," the Connections of His Patrons, and the Politics of Stephen's Reign". The Chaucer Review. 42 (1): 23–47. doi:10.1353/cr.2007.0020. ISSN0009-2002. JSTOR25094383. A terminus ante quern of 1151 might appear at first sight to be supported by references to Adeliza of Louvain, who died in 1151
^Keefe, Thomas K. (1974). "Geoffrey Plantagenet's Will and the Angevin Succession*". Albion. 6 (3): 266–274. doi:10.2307/4048247. ISSN0095-1390. JSTOR4048247. Count Geoffrey Plantagenet's sudden death in September 1151 came at a most inopportune time for his eighteen-year-old son, Henry.