<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified" version="1.0">
  <xs:element name="patron">
    <xs:complexType>
      <xs:choice minOccurs="0" maxOccurs="unbounded">
        <xs:element ref="name"/>
        <xs:element ref="id-num"/>
        <xs:element ref="book"/>
      </xs:choice>
    </xs:complexType>
  </xs:element>
  <xs:element name="name">
    <xs:complexType mixed="true"/>
  </xs:element>
  <xs:element name="id-num">
    <xs:complexType mixed="true"/>
  </xs:element>
  <xs:element name="book">
    <xs:complexType>
      <xs:attribute name="isbn"/>
      <xs:attribute name="title"/>
    </xs:complexType>
  </xs:element>
</xs:schema>