Sitemap/Url/GoogleMultilangUrlDecorator.php
public function addLink($href, $hreflang, $rel = null)
    {
        $this->linkXml .= $this->generateLinkXml($href, $hreflang, $rel);

        return $this;
    }
public function addLink($href, $hreflang, $rel = null)
    {
        $this->linkXml .= $this->generateLinkXml($href, $hreflang, $rel);

        return $this;
    }
public function addLink ( $ href , $ hreflang , $ rel = null ) { $ this -> linkXml .= $ this -> generateLinkXml ( $ href , $ hreflang , $ rel ) ; return $ this ; }
add an alternative language to the url

@param string      $href     Valid url of the translated page
@param string      $hreflang Valid language code @see
http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_LanguageCode
@param string|null $rel      (default is alternate) - valid link type @see
http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_LinkTypes

@return GoogleMultilangUrlDecorator
add an alternative language to the url