private function asVcard($name)
    {
        $name = preg_replace('/\s\s+/i', '', $name); //remove extra white spaces
        $name = preg_replace('/[^A-Za-z0-9\x{002D}\x{002E}\x{00C0}-\x{00FF} -]/', '', $name); //remove special chars
        $name = trim($name); // trim
        $nm_expl = explode(' ', $name);
        $head = '';
        if (in_array($nm_expl[0], array('Prof.', 'Professor', 'Dr.', 'Doutor' ))) {
            $head = array_shift($nm_expl);
        }
        $lastnm = array_pop($nm_expl);
        $n = $lastnm.';'.implode(' ', $nm_expl).';'.$head.';';
        return "BEGIN:VCARD\nVERSION:4.0\nN:$n\nFN:$name\nEND:VCARD";
    }