De Friese hoofdeling opnieuw bekeken. BMGN - Low Countries Historical Review, [S. l.], v. 102, n. 1, p. 1–28, 1987. DOI: 10.18352/bmgn-lchr.2774. Disponível em: https://ojstest.minions.amsterdam/article/view/URN%3ANBN%3ANL%3AUI%3A10-1-103036.. Acesso em: 22 nov. 2024.