How to get the date of registration VK?

Question

PHP

How do I get the registration xml?
I'm trying to use this code:

$get_page = file_get_contents('https://vk.com/foaf.php?id=1');
$data = simplexml_load_file($get_page);
echo "<pre>";
print_r($data);

Returns this:

SimpleXMLElement Object
(
)