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Warnke S, Kemmler S, Hames RS, Tsai HL, Hoffmann-Rohrer U, et al. (2004) Polo-like kinase-2 is required for centriole duplication in mammalian cells. Curr Biol 14: 1200–1207. PLoS ONE | www.plosone.org 11 August 2009 | Volume 4 | Issue 8 | e6752