protected function _getAuthor()
    {
        if ($this->created_by instanceof User) {
            return $this->created_by;
        }

        return new User([
            'username' => __d('content', 'unknown'),
            'name' => __d('content', 'Unknown'),
            'web' => __d('content', '(no website)'),
            'email' => __d('content', 'Unknown'),
        ]);
    }