Wong, Ruth H. K. Educational innovation in Singapore / Ruth H. K. Wong. - París : Ginebra : UNESCO ; OIE, 1974. - 82, [1] p. - Experiments and innovations in education ; 9 . ISBN: 9231011731 No. de Clasificación Universal Decimal: 37. 014. 13: 371.13 (595.13) =20 WON