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Brodack JW, Kilbourn MR, Welch MJ.Brodack JW, et al. Among authors: welch mj.Int J Rad Appl Instrum A. 1988;39(7):689-98. doi: 10.1016/0883-2889(88)90059-7.Int J Rad Appl Instrum A. 1988.PMID: 2844701