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Mathias CJ, Margenau WH, Brodack JW, Welch MJ, Green MA.Mathias CJ, et al.Int J Rad Appl Instrum A. 1991;42(3):317-20. doi: 10.1016/0883-2889(91)90097-k.Int J Rad Appl Instrum A. 1991.PMID: 1647386No abstract available.