code: function(features) {
          var doc;
          if (OpenLayers.Util.isArray(features)) {
              doc = this.createElementNSPlus("atom:feed");
              doc.appendChild(
                  this.createElementNSPlus("atom:title", {
                      value: this.feedTitle
                  })
              );
              for (var i=0, ii=features.length; i<ii; i++) {
                  doc.appendChild(this.buildEntryNode(features[i]));
              }
          }
          else {
              doc = this.buildEntryNode(features);
          }
          return OpenLayers.Format.XML.prototype.write.apply(this, [doc]);
      }
docs: APIMethod: write
  Serialize or more feature nodes to Atom documents.
  
  Parameters:
  features - {<OpenLayers.Feature.Vector>} or Array({<OpenLayers.Feature.Vector>})
  
  Returns:
  {String} an Atom entry document if passed one feature node, or a feed
  document if passed an array of feature nodes.