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Levy M, Morse PK, Liebelt RA, Dallman JJ, McDonald TF.Levy M, et al. Among authors: morse pk.J Med Educ. 1973 Sep;48(9):840-5. doi: 10.1097/00001888-197309000-00007.J Med Educ. 1973.PMID: 4733425No abstract available.