Wójcik, Marek L. “The Unknown Fourteenth-Century Seal of Wieruszów: A Contribution to Research on the Oldest Coats of Arms of the Town and of Its Owners”. Średniowiecze Polskie I Powszechne, vol. 12, Dec. 2020, pp. 69-95, doi:10.31261/SPiP.2020.16.04.