Michel Foucault. . 1972. . The Archaelogy of Knowledge . , Edited by: Sheridan-Smith A. M.. p. 46 London : : Tavistock. .
Michael Cole, Vera John-Stener, Sylvia Scribner and Ellen Souberman. . 1978. . Mind in Society - The Development of Higher Psychological Processes . , p. 24––37. . Cambridge , MA : : Harvard University Press. .