anchor.diff:                labelOk            : labelOk,
                 labelCancel        : labelCancel,
                 axis               : pdc.axis,
  -              onValuesSelected   : function(selectedValues) {
  -                var position = { values: selectedValues };
  -                if (isAlreadyInClassification(position, classifications[startIndex]))
  +              onValuesSelected   : function(positions) {
  +                if (areAlreadyInClassification(positions, classifications[startIndex])) {
                     alert("<fmt:message key='pdcPeas.positionAlreadyExist' bundle='${pdcBundle}'/>");
  -                else
  -                  addPositionInClassifications($elt, position, startIndex, endIndex);
  +                } else {
  +                  addPositionsInClassifications($elt, positions, startIndex, endIndex);
  +                }
                 }
               });
             },
  
positive.code:       }
        
        /**
         * Adds recursively the specified position into the loaded classifications on the PdC between
         * startIndex and endIndex in the array of the imported publication's classifications.
         * If startIndex and endIndex refers the same index, then the position is added only into the
         * classification at this index.
         * Once the position added, the classification rendered within the HTML element $elt is refreshed.
         */
        function addPositionInClassifications($elt, position, startIndex, endIndex) {
          postPosition(classifications[startIndex].uri, position, function(classification) {
            classifications[startIndex] = classification;
            setModified();
            if (endIndex > startIndex) {
              addPositionInClassifications($elt, position, startIndex + 1, endIndex);
            } else {
              $elt.pdcPositions('refresh', classifications[startIndex].positions);
            }
          });
        }
        
        /**
  
negative.code:        * classification at this index.
         * Once the position updated, the classification rendered within the HTML element $elt is refreshed.
         */
        function updatePositionInClassifications($elt, position, newValues, startIndex, endIndex) {
          var location = findPosition(position.values, classifications[startIndex].positions);
          updatePosition(classifications[startIndex].uri, {
            uri: location.position.uri,
            id: location.position.id,
            values: newValues},
          function(classification) {
            classifications[startIndex] = classification;
            setModified();
            if (endIndex > startIndex) {
              updatePositionInClassifications($elt, position, newValues, startIndex + 1, endIndex);
            } else {
              $elt.pdcPositions('refresh', classifications[startIndex].positions);
            }
  