<?xml version="1.0" encoding="ISO-8859-1"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="family" type="family_type">
<xs:key name="sibling_key">
<xs:selector xpath="siblings/sibling"/>
<xs:field xpath="@name"/>
</xs:key>
<xs:keyref name="sibling_key_ref" refer="sibling_key">
<xs:selector xpath="sisters/sister"/>
<xs:field xpath="@name"/>
</xs:keyref>
</xs:element>
<xs:complexType name="family_type">
<xs:sequence>
<xs:element name="siblings" type="siblings_type" />
<xs:element name="sisters" type="sisters_type" />
</xs:sequence>
<xs:attribute name="name" type="xs:string"/>
</xs:complexType>
<xs:complexType name="siblings_type">
<xs:sequence>
<xs:element name="sibling" type="sibling_type" minOccurs="0"
maxOccurs="unbounded" />
</xs:sequence>
</xs:complexType>
<xs:complexType name="sisters_type">
<xs:sequence>
<xs:element name="sister" type="sister_type" minOccurs="0"
maxOccurs="unbounded" />
</xs:sequence>
</xs:complexType>
<xs:complexType name="sibling_type">
<xs:attribute name="name" type="xs:string"/>
</xs:complexType>
<xs:complexType name="sister_type">
<xs:attribute name="name" type="xs:string"/>
</xs:complexType>
</xs:schema>