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Heller SR, Macdonald IA, Herbert M, Tattersall RB.Heller SR, et al. Among authors: tattersall rb.Lancet. 1987 Aug 15;2(8555):359-63. doi: 10.1016/s0140-6736(87)92382-8.Lancet. 1987.PMID: 2886822Clinical Trial.