8Barrows CW. 1981. Roost selection by spotted owls: An adapta?tion to heat stress. The Condor, 83: 302-309.
9Blanco G, Cuevas JA, Fargallo JA. 1998. Breeding density and distribution of Choughs Pyrrhocorax pyrrhocorax nesting in river cliffs: The role of nest-site availability. Ardea, 86: 237-244.
10Boyce MS, Vernier PR, Nielsen SE, et al. 2002. Evaluating resource selection functions. Ecology, 157: 281-300.