E. Gerard, De christelijke arbeidersbeweging in België 1891-1991, I en II. BMGN - Low Countries Historical Review, [S. l.], v. 108, n. 3, p. 523–525, 1993. DOI: 10.18352/bmgn-lchr.3756. Disponível em: https://ojstest.minions.amsterdam/article/view/URN%3ANBN%3ANL%3AUI%3A10-1-104309.. Acesso em: 23 nov. 2024.