private function build_sources_view(Article $article)
 {
     $sources = $article->get_sources();
     $nbr_sources = count($sources);
     if ($nbr_sources) {
         $this->tpl->put('articles.C_SOURCES', $nbr_sources > 0);
         $i = 1;
         foreach ($sources as $name => $url) {
             $this->tpl->assign_block_vars('articles.sources', array('C_SEPARATOR' => $i < $nbr_sources, 'NAME' => $name, 'URL' => $url));
             $i++;
         }
     }
 }