<StructureDefinition xmlns="http://hl7.org/fhir">
  <url value="https://fhir.synapxe.sg/StructureDefinition/ext-ccda-documentreference" />
  <name value="Extension of CCDA Document Reference" />
  <status value="draft" />
  <fhirVersion value="5.0.0" />
  <kind value="complex-type" />
  <abstract value="false" />
  <context>
    <type value="element" />
    <expression value="DocumentReference" />
  </context>
  <type value="Extension" />
  <baseDefinition value="http://hl7.org/fhir/StructureDefinition/Extension" />
  <derivation value="constraint" />
  <differential>
    <element id="Extension.url">
      <path value="Extension.url" />
      <fixedUri value="https://fhir.synapxe.sg/StructureDefinition/ext-ccda-documentreference" />
    </element>
  </differential>
</StructureDefinition>