1. Berg, C., Hertzog, C., & Hunt, E. (1982). Age differences in the speed of mental rotation. Developmental Psychology, 18, 95–107.
2. Bethell-Fox, C. E., & Shepard, R. N. (1988). Mental rotation: Effects of stimulus complexity and familiarity. Journal of Experimental Psychology: Human Perception & Performance, 14, 12–23.
3. Clarkson-Smith, L., & Halpern, D. F. (1983). Can age-related deficits in spatial memory be attenuated through the use of verbal coding? Experimental Aging Research, 9, 179–184.
4. Cooper, L. A., & Shepard, R. N. (1978). Transformations on representation of objects in space. In E. C. Carterette & M. Friedman (Eds.), Handbook of perception (Vol. VIII): Perceptual coding (pp. 105–146). New York: Academic Press.
5. Folk, M. D., & Luce, R. D. (1987). Effects of stimulus complexity on mental rotation rate of polygons. Journal of Experimental Psychology: Human Perception & Performance, 13, 395–404.