1<element name="addressBook" xmlns="http://relaxng.org/ns/structure/1.0"> 2 <zeroOrMore> 3 <element name="card"> 4 <choice> 5 <attribute name="name"> 6 <text/> 7 </attribute> 8 <group> 9 <attribute name="givenName"> 10 <text/> 11 </attribute> 12 <attribute name="familyName"> 13 <text/> 14 </attribute> 15 </group> 16 </choice> 17 <attribute name="email"> 18 <text/> 19 </attribute> 20 </element> 21 </zeroOrMore> 22</element> 23