School Mathematics Project. (1969). SMP Book D. The University Press.
Dyfyniad Arddull ChicagoSchool Mathematics Project. SMP Book D. Cambridge: The University Press, 1969.
Dyfyniad MLASchool Mathematics Project. SMP Book D. The University Press, 1969.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.