77
Sorting in XQuery
<publisher_list>
    FOR $p IN distinct(document("bib.xml")//publisher)
    RETURN <publisher> <name> { $p/text() } </name> ,
                        FOR $b IN document("bib.xml")//book[publisher = $p]
                        RETURN <book>
                                                 {  $b/title ,
                                                     $b/price
                                                  }
                                         </book> SORTBY(price DESCENDING)
                   </publisher> SORTBY(name)
</publisher_list>