# see https://www.google.com/webmasters/tools/docs/en/protocol.html
xml.urlset(:xmlns => "http://www.google.com/schemas/sitemap/0.84") do
    time_zone = TimeZone.new(@site.timezone.current_period.utc_offset)
 	@articles.each do |article|
    xml.url do
      xml.loc("http://#{request.host_with_port}#{request.relative_url_root}#{site.permalink_for(article)}")
      xml.lastmod(article.updated_at.strftime("%Y-%m-%dT%H:%M:%S#{time_zone.formatted_offset}"))
      xml.changefreq("weekly")
    end
  end
end