(1) Peres, Sherwood H. and J. Robert Garcia. 1962. “Validity and Dimensions of Descriptive Adjectives Used in Reference Letters for Engineering Applicants [1],” in Personnel Psychology. 15, 279-286. [1]
(2) Ryan, Michael and David L. Martinson. Spring 2000. “Perceived Effects of Exaggeration in Recommendation Letters,” in Journalism & Mass Communication Educator. 40-52. [2]
Links[1] http://www.researchgate.net/publication/229625031_Validity_and_Dimensions_of_Descriptive_Adjectives_Used_in_Reference_Letters_for_Engineering_Applicants [2] https://www.questia.com/library/journal/1P3-53720808/perceived-effects-of-exaggeration-in-recommendation