Dillström Norgen, V. (1985). The development of the semiotic function: Studies of children's graphic and verbal representations. Uppsala Universitet ; Distributor, Almqvist & Wiksell International.
Chicago-viite (17. p.)Dillström Norgen, Valborg. The Development of the Semiotic Function: Studies of Children's Graphic and Verbal Representations. Uppsala : Stockholm, Sweden: Uppsala Universitet ; Distributor, Almqvist & Wiksell International, 1985.
MLA-viite (8. p.)Dillström Norgen, Valborg. The Development of the Semiotic Function: Studies of Children's Graphic and Verbal Representations. Uppsala Universitet ; Distributor, Almqvist & Wiksell International, 1985.
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