<xsd:group name="MessageHeader.model">
    <xsd:annotation>
        <xsd:documentation xml:lang="en">Defines the structure that contains routing and identification information, which allows processing and transfer of the message. It contains only messaging information that is applicable to all messages. If the information is not message related or is not applicable to all messages then it is not defined in the message header.</xsd:documentation>
    </xsd:annotation>
    <xsd:sequence>
        <xsd:element name="sentBy" type="MessageAddress" minOccurs="0">
            <xsd:annotation>
                <xsd:documentation xml:lang="en">The unique identifier (within its coding scheme) for the originator of a message instance.</xsd:documentation>
            </xsd:annotation>
        </xsd:element>
        <xsd:element name="sendTo" type="MessageAddress" minOccurs="0" maxOccurs="unbounded">
            <xsd:annotation>
                <xsd:documentation xml:lang="en">A unique identifier (within its coding scheme) indicating an intended recipent of a message.</xsd:documentation>
            </xsd:annotation>
        </xsd:element>
        <xsd:element name="copyTo" type="MessageAddress" minOccurs="0" maxOccurs="unbounded">
            <xsd:annotation>
                <xsd:documentation xml:lang="en">A unique identifier (within the specified coding scheme) giving the details of some party to whom a copy of this message will be sent for reference.</xsd:documentation>
            </xsd:annotation>
        </xsd:element>
        <xsd:element name="creationTimestamp" type="xsd:dateTime" minOccurs="0">
            <xsd:annotation>
                <xsd:documentation xml:lang="en">The date and time (on the source system) when this message instance was created.</xsd:documentation>
            </xsd:annotation>
        </xsd:element>
        <xsd:element name="expiryTimestamp" type="xsd:dateTime" minOccurs="0">
            <xsd:annotation>
                <xsd:documentation xml:lang="en">The date and time (on the source system) when this message instance will be considered expired.</xsd:documentation>
            </xsd:annotation>
        </xsd:element>
        <xsd:element name="implementationSpecification" type="ImplementationSpecification" minOccurs="0">
            <xsd:annotation>
                <xsd:documentation xml:lang="en">The version(s) of specifications that the sender asserts the message was developed for.</xsd:documentation>
            </xsd:annotation>
        </xsd:element>
        <xsd:element name="partyMessageInformation" type="PartyMessageInformation" minOccurs="0" maxOccurs="unbounded">
            <xsd:annotation>
                <xsd:documentation xml:lang="en">Additional message information that may be provided by each involved party.</xsd:documentation>
            </xsd:annotation>
        </xsd:element>
        <xsd:element ref="dsig:Signature" minOccurs="0" maxOccurs="unbounded" />
    </xsd:sequence>
</xsd:group>