284964 Bird, M. H. (1991). Mathematics for young children: An active thinking approach. London : Routledge.
Chicago-viite (17. p.)284964 Bird, Marion H. Mathematics for Young Children: An Active Thinking Approach. London : Routledge, 1991.
MLA-viite (9. p.)284964 Bird, Marion H. Mathematics for Young Children: An Active Thinking Approach. London : Routledge, 1991.
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