<?xml version="1.0" encoding="UTF-8"?>
<schema targetNamespace="http://www.example.com/IPO" xmlns:ipo="http://www.example.com/IPO" xmlns="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified">
	<element name="purchaseOrder">
		<complexType>
			<sequence>
				<element name="billTo" type="ipo:Address"/>
			</sequence>
		</complexType>
	</element>
	<complexType name="Address" block="extension">
		<sequence>
			<element name="name" type="string"/>
			<element name="street" type="string"/>
			<element name="city" type="string"/>
		</sequence>
	</complexType>
	<complexType name="USAddress">
		<complexContent>
			<extension base="ipo:Address">
				<sequence>
					<element name="state" type="ipo:USState"/>
					<element name="zip" type="positiveInteger"/>
				</sequence>
			</extension>
		</complexContent>
	</complexType>
	<!-- other Address derivations for more countries -->
	<simpleType name="USState">
		<restriction base="string">
			<enumeration value="AK"/>
			<enumeration value="AL"/>
			<enumeration value="AR"/>
		</restriction>
	</simpleType>
	<!-- simple type definition for UKPostcode -->
</schema>

