<!-- Collection of code snippets by Arne Vajhøj -->
<!-- posted to eksperten.dk, usenet and other places (2002-now) -->
<?php
date_default_timezone_set('Europe/Copenhagen');

// PP style
$dt = date_create();
date_isodate_set($dt, 2009, 33, 1);
echo date_format($dt, 'd/m/Y') . "\r\n";

// OOP style
$dt = new DateTime();
$dt->setISODate(2009, 33, 1);
echo $dt->format('d/m/Y') . "\r\n";
?>