MOL, Johannes Adriaan. Singing nuns and lay sisters in the Frisian houses of the Teutonic Order to 1510. Ordines Militares Colloquia Torunensia Historica. Yearbook for the Study of the Military Orders. Online. 30 December 2024. Vol. 29, pp. 313-335. [Accessed 1 February 2026]. DOI 10.12775/OM.2024.013.