hi

<xs:element name="hi">
  <xs:complexType mixed="true">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:element ref="bpt"/>
      <xs:element ref="ept"/>
      <xs:element ref="it"/>
      <xs:element ref="ph"/>
      <xs:element ref="hi"/>
      <xs:element ref="ut"/>
    </xs:choice>
    <xs:attribute name="x"/>
    <xs:attribute name="type"/>
  </xs:complexType>
</xs:element>