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Papanikolaou N, Mackie TR, Meger-Wells C, Gehring M, Reckwerdt P.Papanikolaou N, et al. Among authors: mackie tr.Med Phys. 1993 Sep-Oct;20(5):1327-36. doi: 10.1118/1.597154.Med Phys. 1993.PMID: 8289713