Roman Michałowski: The Gniezno Summit. The Religious Premises of the Founding of the Archbishopric of Gniezno. Zeitschrift für Ostmitteleuropa-Forschung, [S. l.], v. 67, n. 3, p. 465–465, 2018. DOI: 10.25627/201867310459. Disponível em: https://openjournals.osmikon.de/zfo/article/view/10459. Acesso em: 16 sep. 2026.