<?xml version="1.0"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    targetNamespace = "http://xsdtesting"
    xmlns:x = "http://xsdtesting"
    elementFormDefault = "qualified"
    attributeFormDefault = "qualified"
>

<!-- 
use=optional, fixed="37" (may appear once, if appear, value must be "37"), instant xml value =37
-->

<xsd:complexType name="attRef">
   <xsd:attribute name="att" use="optional" fixed="37"/>
</xsd:complexType>

<xsd:element name="doc">
    <xsd:complexType>
            <xsd:choice>
                <xsd:element name="elem" type="x:attRef">
                </xsd:element>
            </xsd:choice>
    </xsd:complexType>
</xsd:element>

</xsd:schema>
