1. Learned helplessness in humans: Critique and reformulation;Abramson;Journal of Abnormal Psychology,1978
2. Toward an understanding of inequity;Adams;Journal of Abnormal and Social Psychology,1963
3. Children as teachers: Theory and research on tutoring;Allen,1976
4. Reactions to help in peer tutoring: roles and social identities;Allen,1983
5. Help seeking and achievement motivation: Perspectives from attribution theory;Ames,1983