DONALDSON, M Positive and negative information in matching problems. [electronic resource] - British journal of psychology (London, England : 1953) Aug 1959 - 253-62 p. digital Publication Type: Journal Article ISSN: 0007-1269 Standard No.: 10.1111/j.2044-8295.1959.tb00702.x doi Subjects--Topical Terms: HumansThinking