public function unsubscribeFormAction( $email = NULL )
    {
        $address = $this->addressRepository->findOneByEmail($email);

        if ($email != NULL) {
            $this->view->assign('email', $email);
        }
        if ($address) {
            $data = [
                'address' => $address,
                'hash' => $address->getRegisteraddresshash()
            ];

            $mailTemplate = 'Address/MailNewsletterUnsubscribe';
            $this->sendResponseMail(
                $address->getEmail(),
                $mailTemplate,
                $data,
                $this->settings['mailformat'],
                LocalizationUtility::translate('mail.unsubscribe.subjectsuffix', 'registeraddress')
            );

            $this->view->assign('address', $address);
        }
    }