1Polanyi, M. , The Study of Man. London : Routledge & Kegan Paul,c1957,p12, p18.
2Sternberg, R. J. , What Do We Know About Tacit Knowledge? Making the Tacit Become Explicit, see Sternberg, R. J. & Horvath, J. A. ,ed. ,Tacit Knowledge in Professional Praetice:Researcher and Practitioner Perspectives,London:Lawrence Erlbaum Associates inc. c1999,p236.