<?xml version="1.0" standalone="yes"?>
<!DOCTYPE range[
	<!ELEMENT range (product,price)+>
	<!ELEMENT product (#PCDATA)>
	<!ATTLIST product code ID #REQUIRED>
	<!ELEMENT price (#PCDATA)>
	<!ATTLIST product code-ref IDREF #IMPLIED>
]>
<range>
	<product code="S123">Stanley screwdriver</product>
	<price code-ref="S123">$7.99</price>

	<product code="B765">Bosch drill</product>
	<price code-ref="B765">$39.95</price>
</range>
