标题：812 精神薄弱児の数操作能力について(21.精神薄弱(2),日本教育心理学会第5回総会部門別研究発表要旨・討論の概要) [in Japanese] 812 On the mathematical ability of feeble-minded children(21.Mental deficienty (2),PROCEEDINGS OF THE FIFTH ANNUAL CONVENTION OF JAPANESE ASSOCIATION OF EDUCATIONAL PSYCHOLOGY PAPERS AND THE SUMMARIES OF DISCUSSIONS) [in Japanese]
