1936. p. 5. Libro de Actas de 1937 (in Spanish). Diputación de Cantabria. Ruiz Martínez, J.R. (1985). Consejo Interprovincial de Santander, Palencia y Burgos
visited the settlement, proposed to the Viceroy the reactivation of the Olazarán mine, which was abandoned in the Boca de Caballeros, since this measure