docs: public void setModel (PropertySheetModel pm)
    {
      if (pm instanceof org.apache.ojb.tools.mapping.reversedb.DBFKRelation)
      {
        this.aRelation = (org.apache.ojb.tools.mapping.reversedb.DBFKRelation)pm;
        this.readValuesFromReference();
      }
      else
        throw new IllegalArgumentException();    
    }