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Eisenhut M, Liefhold J.Eisenhut M, et al. Among authors: liefhold j.Int J Rad Appl Instrum A. 1988;39(7):639-49. doi: 10.1016/0883-2889(88)90052-4.Int J Rad Appl Instrum A. 1988.PMID: 2844699