versionType

<xsd:simpleType name="versionType" id="st.versionType">
  <xsd:annotation>
    <xsd:documentation>
      <h:div class="summary">Version of a doc or code.</h:div>
      <h:div class="description">Forms include 1, 0.9, 1.1.3, 1.2alpha, etc.</h:div>
      <h:div class="example" href="version1.xml"/>
    </xsd:documentation>
  </xsd:annotation>
  <xsd:restriction base="xsd:string">
    <xsd:pattern value="[0-9]+(\.[0-9]+[A-Za-z0-9\.\-_]*)*"/>
  </xsd:restriction>
</xsd:simpleType>