PHP: Convert ETRS89 UTM33 (EPSG: 25833) to WGS84 coordinates

<?php
// first:
// $ composer require php-coord/php-coord
 
require_once __DIR__ . '/vendor/autoload.php';
 
$UTMRef = new \PHPCoord\UTMRef(350531.8, 5689109.2, 0, 'N', 33);
$LatLng = $UTMRef->toLatLng();
 
echo (string) $UTMRef . "\n";
echo (string) $LatLng . "\n";
?>