UNDERHILL, R. G. (1977). Teaching elementary school mathematics.-- ed.2. Charles E.Merill pub.
Chicago-čujuhus (17. p.)UNDERHILL, Robert G. Teaching Elementary School Mathematics.-- Ed.2. Columbus: Charles E.Merill pub, 1977.
MLA-čujuhus (9. p.)UNDERHILL, Robert G. Teaching Elementary School Mathematics.-- Ed.2. Charles E.Merill pub, 1977.
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