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Marsh JN, Hughes MS, Brandenburger GH, Miller JG.Marsh JN, et al. Among authors: hughes ms.Ultrasound Med Biol. 1999 Oct;25(8):1321-4. doi: 10.1016/s0301-5629(99)00077-0.Ultrasound Med Biol. 1999.PMID: 10576274