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Schroder، F. H.؛ Kruger، A. B.؛ Rietbergen، J.؛ Kranse، R.؛ Maas، P. v. d.؛ Beemsterboer، P.؛ Hoedemaeker، R. (1998). "Evaluation of the Digital Rectal Examination as a Screening Test for Prostate Cancer". JNCI Journal of the National Cancer Institute. ج. 90 ع. 23: 1817–1823. DOI:10.1093/jnci/90.23.1817. ISSN:0027-8874.