public function permalinksByLanguage($language = null)
    {
        $result = array();

        if (null === $language) {
            $language = $this->currentLanguage;
        }

        foreach ($this->pages as $page) {
            foreach ($page["seo"] as $pageAttribute) {
                if ($pageAttribute["language"] != $language) {
                    continue;
                }

                $result[] = $pageAttribute["permalink"];
            }
        }

        return $result;
    }