code: public function findLastVersionByLanguage($siteId, $language)
      {
          $qa = $this->createAggregationQuery();
          $qa->match(
              array(
                  'siteId' => $siteId,
                  'deleted' => false,
                  'language' => $language
              )
          );
  
          return $this->findLastVersion($qa);
      }
docs: @param string $siteId
  @param string $language
  
  @return array