<xsd:complexType name='bookType'>
    <xsd:sequence>
	<xsd:element name='author' 	type='s:author'/>
	<xsd:element name='title'	type='string'/>
	<xsd:element name='publisher' 	type='string'/>

	<xsd:choice>
		<xsd:element name='year' 	type='gYear'/>
		<xsd:element name='date' 	type='date'/> 
	</xsd:choice>

    </xsd:sequence>

    <xsd:attribute name='id'		type='string'/>
</xsd:complexType>