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Tyras DH, Ahmad N, Kaiser GC, Barner HB, Codd JE, Willman VL.Tyras DH, et al. Among authors: willman vl.Ann Thorac Surg. 1979 Jun;27(6):547-53. doi: 10.1016/s0003-4975(10)63368-1.Ann Thorac Surg. 1979.PMID: 313199