1<element name="addressBook" xmlns="http://relaxng.org/ns/structure/1.0">
2  <oneOrMore>
3    <element name="card">
4      <element name="name">
5        <text/>
6      </element>
7      <element name="email">
8        <text/>
9      </element>
10    </element>
11  </oneOrMore>
12</element>
13