1. Poincaré, H. (1913) The Foundations of Science: Science and Hypothesis, The Value of Science, Science and Method (trans. G. B. Halsted), Science Press, New York and Garrison, NY.
2. Pribram, K.H. and Gill, M.M. (1976) Freud’s ‘Project’ Re-assessed: Preface to Contemporary Cognitive Theory and Neuropsychology, Basic Books, New York.
3. Kris, E. (1952) Psychoanalytic Explorations in Art, International Universities Press, New York.
4. Bastick, T. (1982) Intuition: How We Think and Act, John Wiley and Sons, Chich-ester, New York, Brisbane, Toronto and Singapore.
5. Weisberg, R.W. (1993) Creativity: Beyond the Myth of Genius, W. H. Freeman, New York.