National Council of Teachers of Mathematics, Cooney, T. J., & Hirsch, C. R. (1990). Teaching and learning mathematics in the 1990s. NCTM.
Cita Chicago (17th ed.)National Council of Teachers of Mathematics, Thomas J. Cooney, i Christian R. Hirsch. Teaching and Learning Mathematics in the 1990s. Reston, VA: NCTM, 1990.
Cita MLA (9th ed.)National Council of Teachers of Mathematics, et al. Teaching and Learning Mathematics in the 1990s. NCTM, 1990.
Atenció: Aquestes cites poden no estar 100% correctes.