open 930168.xml ;
register-namespace ce 'http://put-your-namespace-URI-here' ;
for /ce:bib/ce:bib-reference/ce:other-ref/ce:textref {
    my $label = substring-before(.,'),') ;
    if ($label and xsh:matches($label,'\d{4}$')) {
        insert element ce:label prepend ../.. ;
        insert text concat($label, ')') into ../../ce:label[1] ;
    }
}
save :b ;