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Volk RJ, Cantor SB, Steinbauer JR, Cass AR.Volk RJ, et al. Among authors: cantor sb.J Gen Intern Med. 1997 Dec;12(12):763-9. doi: 10.1046/j.1525-1497.1997.07162.x.J Gen Intern Med. 1997.PMID: 9436896Free PMC article.