Leitzel, J. R. C. (1991). A call for change: Recommendations for the mathematical preparation of teachers of mathematics. The Mathematical Association of America.
Chicago-čujuhus (17. p.)Leitzel, James R. C. A Call for Change: Recommendations for the Mathematical Preparation of Teachers of Mathematics. Washington, D.C: The Mathematical Association of America, 1991.
MLA-čujuhus (9. p.)Leitzel, James R. C. A Call for Change: Recommendations for the Mathematical Preparation of Teachers of Mathematics. The Mathematical Association of America, 1991.
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