1. Feedback and human behavior;Annett,1969
2. Making work worthwhile;Bingham,1932
3. The effects of contingent and noncontingent rewards and controls on intrinsic motivation;Deci;Organizational Behavior and Human Performance,1972
4. Employee reactions to job characteristics;Hackman;Journal of Applied Psychology,1971
5. A method for judging all possible contrasts in the analysis of variance;Scheffé;Biometrika,1953