$Revision$
$Date$
co — The location of a callout embedded in text
co ::= EMPTY
| 
                         Name  | 
                     
                         Type  | 
                     
                         Default  | 
                  
| label | CDATA | None | 
| linkends | IDREFS | None | 
A CO identifies (by its location) a point of
               reference for a callout.  See Callout.
               
            
These elements contain co:
                  computeroutput, literallayout, programlisting, prompt, replaceable, screen, synopsis, systemitem, userinput.
               
areaspec, calloutlist, coref, graphicco, imageobjectco, mediaobjectco, programlistingco, screenco.