<xs:attributeGroup name="LoyaltyCertificateGroup">
    <xs:annotation>
        <xs:documentation xml:lang="en">Identifies the Loyalty Program, membership, form factor used by the certificate and its current status</xs:documentation>
    </xs:annotation>
    <xs:attributeGroup ref="ID_OptionalGroup">
        <xs:annotation>
            <xs:documentation xml:lang="en">Identifies the individual program or promotion within a loyalty scheme</xs:documentation>
        </xs:annotation>
    </xs:attributeGroup>
    <xs:attribute name="ID_Context" type="StringLength1to32" use="optional">
        <xs:annotation>
            <xs:documentation xml:lang="en">Identifies the source of the code that identifies program or promotion within a loyalty scheme</xs:documentation>
        </xs:annotation>
    </xs:attribute>
    <xs:attributeGroup ref="LoyaltyCertificateNumberGroup">
        <xs:annotation>
            <xs:documentation xml:lang="en">Identifies the unique certificate number and the loyalty program and the membership ID associated with this certificate</xs:documentation>
        </xs:annotation>
    </xs:attributeGroup>
    <xs:attributeGroup ref="EffectiveExpireOptionalDateGroup">
        <xs:annotation>
            <xs:documentation xml:lang="en">Identifies either the date range when the Certificate is valid or the dates against which the certificate is being applied</xs:documentation>
        </xs:annotation>
    </xs:attributeGroup>
    <xs:attribute name="NmbrOfNights" type="xs:nonNegativeInteger" use="optional">
        <xs:annotation>
            <xs:documentation xml:lang="en">The number of nights of the hotel stay that are used to calculate the redemption amount.</xs:documentation>
        </xs:annotation>
    </xs:attribute>
    <xs:attribute name="Format" use="optional">
        <xs:annotation>
            <xs:documentation xml:lang="en">Indicates what form the certificate is in e.g. Paper or Electronic</xs:documentation>
        </xs:annotation>
        <xs:simpleType>
            <xs:restriction base="xs:NMTOKEN">
                <xs:enumeration value="Paper" />
                <xs:enumeration value="Electronic" />
            </xs:restriction>
        </xs:simpleType>
    </xs:attribute>
    <xs:attribute name="Status" type="StringLength1to16" use="optional">
        <xs:annotation>
            <xs:documentation xml:lang="en">Used to define the status of the certificate e.g. Available, Voided, Cancelled, Reserved, Used.</xs:documentation>
        </xs:annotation>
    </xs:attribute>
</xs:attributeGroup>