KNOTTER, Ad. Ten geleide. Studies over de sociaaleconomische geschiedenis van Limburg, [S. l.], v. 60, p. 6–9, 2015. DOI: 10.58484/ssegl.v60i12399. Disponível em: https://testplatform.openjournals.nl/SSEGL/article/view/12399. Acesso em: 11 apr. 2026.