Christianising a Country: A Genuine Act of Faith or an Exercise in Political Opportunism? On (Questioning) the Authenticity of Medieval Political Conversions — the Case of Poland - Cebula, Adam (. Journal of religious history. - Oxford : Wiley-Blackwell, 1960-. - Online-Ressource. - ISSN 1467-9809. - DOI 10.1111/(ISSN)1467-9809 43, 2019)