<?xml version="1.0"?>

<!DOCTYPE bibliography SYSTEM "http://somewhere.net/book.dtd">

<bibliography>
<book>
	<author>
		<firstname>John Maynard</firstname>
		<lastname>Keynes</lastname>
	</author>
	<title>The General Theory of Employment, Interest and Money</title>
	<publisher>Macmillan</publisher>
</book>
</bibliography>

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<!ELEMENT book (author, title, publisher, year?)>

<!ELEMENT author (firstname, lastname)>

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