/fr/sciences-et-techniques-c17-p1.html
  (8) Undefined index: lang   SiteListModel.php   line 266     21-11-17   14:53
FrontController->dispatch() # line   17, file: /var/www/netref.info/index.php
  call_user_func_array(Array[2], Array[3]) # line  220, file: /var/www/netref.info/core/FrontController.php
    SiteController->categoryAction("17", "sciences-et-techniques", "1") # line    0, file: unknown
      SiteListModel->getValidatedSitesInCategory("17", "1") # line  145, file: /var/www/netref.info/controllers/SiteController.php