LINSSEN, Georges. Dr. Rudolf Philips 80 jaar. Studies over de sociaaleconomische geschiedenis van Limburg, [S. l.], v. 50, p. 5–38, 2005. DOI: 10.58484/ssegl.v50i12513. Disponível em: https://testplatform.openjournals.nl/SSEGL/article/view/12513. Acesso em: 11 apr. 2026.