1. Locke, J. An Essay Concerning Human Understanding (Basset, London, 1690).
2. Berkeley, G. An Essay Toward a New Theory of Vision (Pepyat, Dublin, 1709).
3. Piaget, J. The Origins of Intelligence (Norton, New York, 1952); The Construction of Reality (Basic, New York, 1954); Play, Dreams and Imitation in Childhood (Norton, New York, 1962).
4. Gibson, J. J. The Senses Considered as Perceptual Systems (Houghton Mifflin, New York, 1966).
5. Gibson, E. J. Principles of Perceptual Learning and Development (Appleton-Century-Crofts, New York, 1969).