Duda, M. et al. 2022. Activities of a Teutonic Spy Nicknamed “N.S. Arman” in the Kingdom of Poland in the Mid-Fifteenth Century and its Identity. Średniowiecze Polskie i Powszechne. 14, (Dec. 2022), 237–274. DOI:https://doi.org/10.31261/SPiP.2022.18.11.