Attributes / relations provided by
♦ 1Balda, Russell P. and Kamil, Alan,
Linking Life Zones, Life History Traits, Ecology, and Spatial Cognition in Four Allopatric Southwestern Seed Caching Corvids (2006). Papers in Behavior and Biological Sciences. Paper 36.
♦ 2Spermophilus variegatus, Emily C. Oaks, Paul J. Young, Gordon L. Kirkland, Jr., and David F. Schmidt, MAMMALIAN SPECIES No. 272, pp. 1-8 (1987)