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<?php $givenday = mktime(0,0,0,01,01,2013); $Monday = strtotime("Monday this week",$givenday); echo date("j M Y H:i:s", $Monday); function StartOfWeek($year, $week) { $Jan1 = mktime(1,1,1,1,1,$year); $MondayOffset = (11-date('w',$Jan1))%7-3; $desiredMonday = strtotime(($week-1) . ' weeks '.$MondayOffset.' days', $Jan1); return $desiredMonday; } echo StartOfWeek(2013, 1);

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