标题：813 精薄児の数概念 : 行動様式による検討(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] 813 Number concept of mentally defective children : An approach from their behavior pattern(21.Mental deficienty (2),PROCEEDINGS OF THE FIFTH ANNUAL CONVENTION OF JAPANESE ASSOCIATION OF EDUCATIONAL PSYCHOLOGY PAPERS AND THE SUMMARIES OF DISCUSSIONS) [in Japanese]
