López Vera, F., and B. López-Camacho. “Historical Water Supply to The Monastery of El Paular: A ‘qanat’ in the Guadarrama Mountain Range (Madrid, Spain)”. Boletín Geológico Y Minero, vol. 128, no. 1, Mar. 2017, pp. 193-06, doi:10.21701/bolgeomin.128.1.011.