function getArticleCountries(order_by){
 var req = new JsHttpRequest();
 req.onreadystatechange = function()
 {
  if (req.readyState == 4){
   if (req.responseJS){
   document.getElementById('cntr').innerHTML = req.responseJS.html_countries_list;
   setCountrySortingButton(req.responseJS.order_by);
   document.getElementById('cntr').scrollTop = 0;
  }
 }
 }

 req.open('GET', 'http://' + DOMAIN_NAME + '/index.php?module=country_article', true);
 req.send({'action':'ajax_get_countries_by_' + order_by});
}