<xs:attribute name="halign" type="left-center-right"/>

<xs:attributeGroup name="halign">
  <xs:annotation>
    <xs:documentation>In cases where text extends over more than one line, horizontal alignment and justify values can be different. The most typical case is for credits, such as: Words and music by Pat Songwriter Typically this type of credit is aligned to the right, so that the position information refers to the right-most part of the text. But in this example, the text is center-justified, not right-justified. The halign attribute is used in these situations. If it is not present, its value is the same as for the justify attribute.</xs:documentation>
  </xs:annotation>
  <xs:attribute name="halign" type="left-center-right"/>
</xs:attributeGroup>