Suggestion to improve an XML syntax tree

At the start of Part 1: Section 3 'Types' is the following XML syntax tree:

<description>
  <types>
    <documentation />*
    [extension elements]*
  </types>
</description>

In the WSDL 2.0 Primer, Section 2.3 'More on Message Types', the following
more descriptive XML syntax tree is used:

<description>
<types>
<documentation />?
<xs:import namespace="xs:anyURI" schemaLocation= "xs:anyURI"?/>*
<xs:schema targetNamespace="xs:anyURI" />*

[extension elements]*
</types>
</description>

Perhaps Part 1: Section 3 'Types' should use the same XML syntax tree
that's used in the Primer, especially as it goes on to discuss <xs:import>
and <xs:schema>.

regards,
John Kaputin