References
- Harleston , B. W. and Cunningham , S. M. 1961 . Task difficulty and anxiety level as factors affecting performance in a verbal learning situation . J. of Psychol. , 52 : 77 – 86 .
- Noble , C. E. 1961 . “ Verbal learning and individual differences ” . In Verbal Learning and Verbal Behavior , Edited by: Cofer , C. New York : McGraw-Hill .