Rebollo, S., Robles, L. y Gómez-Sal, A. (1993) «The influence of livestock management on land use competition between domestic and wild ungulates: sheep and chamois Rupicapra pyrenaica parva Cabrera in the Cantabrian range», Pirineos, 141-142, pp. 47–62. doi: 10.3989/pirineos.1993.v141-142.163.