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Burkart DJ, Johnson CD, Ehman RL.Burkart DJ, et al. Among authors: ehman rl.AJR Am J Roentgenol. 1993 Dec;161(6):1279-82. doi: 10.2214/ajr.161.6.8249742.AJR Am J Roentgenol. 1993.PMID: 8249742