Shape discrimination by goldfish: Coding of irregularities.

[1]  N S Sutherland,et al.  Discrimination of Circles and Squares with and without Knobs by Goldfish , 1969, The Quarterly journal of experimental psychology.

[2]  N. Sutherland,et al.  Visual discrimination by the goldfish: The orientation of rectangles , 1963 .

[3]  N. Sutherland.  Outlines of a theory of visual pattern recognition in animals and man , 1968, Proceedings of the Royal Society of London. Series B. Biological Sciences.

[4]  N. Sutherland,et al.  Shape discrimination in rat, octopus, and goldfish: a comparative study. , 1969, Journal of comparative and physiological psychology.