<xs:element name="catalogRef">
    <xs:annotation>
        <xs:documentation>A reference to a remote catalog. A hyperlink to a set of scheme alias declarations.</xs:documentation>
    </xs:annotation>
    <xs:complexType>
        <xs:sequence>
            <xs:element ref="title" minOccurs="0" maxOccurs="unbounded">
                <xs:annotation>
                    <xs:documentation>A short natural language name for the catalog.</xs:documentation>
                </xs:annotation>
            </xs:element>
        </xs:sequence>
        <xs:attribute name="href" type="IRIType" use="required">
            <xs:annotation>
                <xs:documentation>A hyperlink to a remote Catalog.</xs:documentation>
            </xs:annotation>
        </xs:attribute>
        <xs:anyAttribute namespace="##other" processContents="lax">
            <xs:annotation>
                <xs:documentation>Any other attributes from other namespaces.</xs:documentation>
            </xs:annotation>
        </xs:anyAttribute>
    </xs:complexType>
</xs:element>