ABMA, R. Het Plan van de arbeid en de SDAP. BMGN - Low Countries Historical Review, [S. l.], v. 92, n. 1, p. 37–68, 1977. DOI: 10.18352/bmgn-lchr.1968. Disponível em: https://bmgn-lchr.nl/article/view/URN%3ANBN%3ANL%3AUI%3A10-1-102130. Acesso em: 26 apr. 2024.