Pérez Castroviejo, Pedro M. “The Social Welfare in Biscay: Origin and Development of the First Social Insurances, 1900-1936”. Revista de Historia Industrial — Industrial History Review 20, no. 45 (December 21, 2017): 43–78. Accessed April 28, 2024. https://revistes.ub.edu/index.php/HistoriaIndustrial/article/view/20787.