Não informado. (1994). Teaching Children Mathematics. National Council of Teachers of Mathematics.
Citação do estilo Chicago (17ª ed.)Não informado. Teaching Children Mathematics. Reston, Va: National Council of Teachers of Mathematics, 1994.
Citação MLA (8ª ed.)Não informado. Teaching Children Mathematics. National Council of Teachers of Mathematics, 1994.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.