Th.S.B. Johnston, Codex Hummercensis (Groningen, UB, PEIP 12). An old Frisian legal manuscript in Low Saxon guise. BMGN - Low Countries Historical Review, [S. l.], v. 114, n. 4, p. 589–591, 1999. DOI: 10.18352/bmgn-lchr.5099. Disponível em: https://bmgn-lchr.nl/article/view/URN%3ANBN%3ANL%3AUI%3A10-1-105846.. Acesso em: 18 jul. 2024.