↑Morris, R.G.M. (May 1981). "Spatial localization does not require the presence of local cues". Learning and Motivation. 12 (2): 239–260. doi:10.1016/0023-9690(81)90020-5.
↑Andersen, P; Morris, R; Amaral, D; Bliss, T; O'Keefe, J, eds. (2007). The Hippocampus Book. Oxford, United Kingdom: Oxford University Press. pp. xx+832. ISBN978-0-19-510027-3. OCLC64444087.