Book, W. F. (1932). Economy and technique of learning. D. C. Heath.
Dyfyniad Arddull ChicagoBook, William Frederick. Economy and Technique of Learning. Boston: D. C. Heath, 1932.
Dyfyniad MLABook, William Frederick. Economy and Technique of Learning. D. C. Heath, 1932.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.