Cita APA (7a ed.)

Trafton, P. R. (1989). New directions for elementary school mathematics. National Council of Teachers of Mathematics.

Cita Chicago Style (17a ed.)

Trafton, Paul R. New Directions for Elementary School Mathematics. Reston, Va.: National Council of Teachers of Mathematics, 1989.

Cita MLA (8a ed.)

Trafton, Paul R. New Directions for Elementary School Mathematics. National Council of Teachers of Mathematics, 1989.