private function removeReferenceItemInArray(array &$room)
    {
        $roomCopy = $room;
        $keys = array_keys($room);
        foreach ($keys as $key) {
            if (is_array($roomCopy[$key])) {
                $roomCopy[$key]['_test'] = true;
                if (isset($room[$key]['_test'])) {
                    // It's a reference
                    unset($room[$key]);
                }
            }
        }
    }