P.F. Maas, Kabinetsformaties 1959-1973. BMGN - Low Countries Historical Review, [S. l.], v. 100, n. 2, p. 330–333, 1985. DOI: 10.18352/bmgn-lchr.2622. Disponível em: https://ojstest.minions.amsterdam/article/view/URN%3ANBN%3ANL%3AUI%3A10-1-102847.. Acesso em: 22 dec. 2024.