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    17 Nov 2012
    00:08 GMT
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    Media Coverage of This Article Posted by PLOS_ONE_Group on 17 Nov 2012 at 00:08 GMT
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    06 Dec 2008
    14:53 GMT
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    Internal and External Validity Posted by plostrac on 24 Oct 2008 at 18:42 GMT
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    10 Oct 2008
    01:17 GMT
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    ? Posted by atalienay2 on 10 Oct 2008 at 01:17 GMT
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    03 Oct 2008
    22:52 GMT
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    Excellent study. Posted by mcoogan on 03 Oct 2008 at 22:52 GMT