Bernardinello, Stefano. “The Relationships Between the «Ruling Classes» and the Cities of the Po Valley (Mid-11th-Mid-12th Centuries): Summary of a Research Path and First Notes for a New One”. Studi di storia medioevale e di diplomatica - Nuova Serie, no. 3 (December 18, 2019): 5–42. Accessed June 30, 2024. https://riviste.unimi.it/index.php/SSMD/article/view/12577.