Ross, C. C. (1947). Measurement in today's schools (2d ed.). s.n.
Dyfyniad Arddull ChicagoRoss, Clay Campbell. Measurement in Today's Schools. 2d ed. New York: s.n, 1947.
Dyfyniad MLARoss, Clay Campbell. Measurement in Today's Schools. 2d ed. s.n, 1947.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.