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Ludlum E, Mu G, Weinberg V, Roach M 3rd, Verhey LJ, Xia P.Ludlum E, et al. Among authors: weinberg v.Med Phys. 2007 Dec;34(12):4750-6. doi: 10.1118/1.2804579.Med Phys. 2007.PMID: 18196802