Graaf Willem I van Holland (1202-1222): ridderschap en machtspolitiek. BMGN - Low Countries Historical Review, [S. l.], v. 116, n. 2, p. 141–161, 2001. DOI: 10.18352/bmgn-lchr.5448. Disponível em: https://ojstest.minions.amsterdam/article/view/URN%3ANBN%3ANL%3AUI%3A10-1-106256.. Acesso em: 22 nov. 2024.