WD-query-algebra-20010215 2.13 sorting ? missing /data()

the example

    sort b in review0/book by b/title
              ==> book [ title  [ "Data on the Web" ], 
                         review [ "This is great!" ] ], 
                  book [ title  [ "XML Query" ], 
                         review [ "This is pretty good too!" ] ]
              :   book [ title [ String ], review [ String ] ] ] {0, *}

would appear to be missing a concluding data() operator, as in

     sort b in review0/book by b/title/data()

?
wouldn't the given example sort based on global order instead?