1. Berkeley, G.: 1709,An Essay Towards A New Theory of Vision, reprinted in George Berkeley,Philosophical Works, J. M. Dent, London, 1975.
2. Cornsweet, T.: 1970,Visual Perception, Academic Press, New York.
3. Dretske, F.: 1981,Knowledge and the Flow of Information, MIT Press, Cambridge, Massachusetts.
4. Goodman, N.: 1977,The Structure of Appearance, 3rd ed., D. Reidel, Dordrecht.
5. Goodman, N.: 1978,Ways of Worldmaking, Hackett Publishing Company, Indianapolis.