Cofman, J. (1995). Numbers and shapes revisited: More problems for young mathematicians. Clarendon Press.
Chicago-viite (17. p.)Cofman, Judita. Numbers and Shapes Revisited: More Problems for Young Mathematicians. Oxford: Clarendon Press, 1995.
MLA-viite (9. p.)Cofman, Judita. Numbers and Shapes Revisited: More Problems for Young Mathematicians. Clarendon Press, 1995.
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