XQuery order by ascending and descending

In XQuery, How do you order by ascending and descending?

I have got the following from a tutorial:

for $x in doc("books.xml")/bookstore/book
where $x/price>30
order by $x/title
return $x/title

would it be

for $x in doc("books.xml")/bookstore/book
where $x/price>30
order by $x/title ascending
return $x/title