<xs:schema
   xmlns:xs="http://www.w3.org/2001/XMLSchema"
   xmlns:mt="http://openuri.org/typesonly"
   targetNamespace="http://openuri.org/typesonly"
   elementFormDefault="qualified"
   attributeFormDefault="unqualified" >

  <xs:complexType name="person">
    <xs:sequence>
      <xs:element name="firstname" type="xs:string"/>
      <xs:choice>
        <xs:element name="age">
           <xs:simpleType>
             <xs:restriction base="xs:integer">
               <xs:minInclusive value="1"/>
               <xs:maxInclusive value="100"/>
             </xs:restriction>
           </xs:simpleType>
        </xs:element>
        <xs:element name="birthday" type="xs:date"/>
      </xs:choice>
        
      <xs:element minOccurs="0" maxOccurs="unbounded" type="mt:person" name="child"/>
    </xs:sequence>
      
    <xs:attribute name="gender">
      <xs:simpleType>
        <xs:restriction base="xs:NMTOKEN">
          <xs:enumeration value="male"/>
          <xs:enumeration value="female"/>
        </xs:restriction>
      </xs:simpleType>
    </xs:attribute>
      
  </xs:complexType>

  <xs:element name="record" type="mt:person"/>
  
  <xs:simpleType name="State">
    <xs:restriction base="xs:string">
      <xs:enumeration value="AK"/>
      <xs:enumeration value="AL"/>
      <xs:enumeration value="AS"/>
      <xs:enumeration value="AZ"/>
    </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="ListOfStates">
    <xs:list itemType="mt:State"/>
  </xs:simpleType>
  
  <xs:complexType name="candidate">
    <xs:sequence>
      <xs:element name="name" type="xs:string"/>
      <xs:element name="states" type="mt:ListOfStates"/>
    </xs:sequence>
  </xs:complexType>
  
</xs:schema>