public function listVerifiedEmailAddresses() {
        $response = $this->_makeRequest(array(
            'Action' => 'ListVerifiedEmailAddresses'
        ));
        $dom = new DOMDocument();
        $dom->loadXML($response);
        $members = $dom->getElementsByTagName('member');
        $out = array();
        foreach ($members as $member) {
            $out[] = $member->nodeValue;
        }
        return $out;
    }