how to solve this - unique- identifying the unique ite

Hi all,

What i want to do is 
1.  select  a book which has the bookproperty element and try matching each of the other book with the same Name and ID value. If it matches I should print the book block with the the bookproperty. discard the other book with the matching Name and ID without the bookproperty element.
2. If the book element block is without the matching book subelement Name and ID  value with the subelement bookproperty print the book element block as such.
3.  If the book element block is with the subelement bookproperty  and with no matching Name and ID Value then print the  book block with the  subelement
bookproperty.

If I have not explained clearly see the example below.

Thanks in advance for any direction to solve this.
Ram

Here is the input xml.
<!-- Input -->
<?xml version="1.0" encoding="UTF-8"?>
<Item>
	<book>
		<Name>t </Name>
		<ID>t1</ID>
		<bookproperty>
			<lang>en </lang>
			<text>string1</text>
		</bookproperty>
	</book>
	<book>
		<Name>t </Name>
		<ID>t1</ID>
	</book>
	<book>
		<Name>x</Name>
		<ID>x1</ID>
		<bookproperty>
			<lang>tn</lang>
			<text>string2</text>
		</bookproperty>
	</book>
.....
</Item>


<!--OUtPUT-->

<Item>
	<book>
		<Name>t</Name>
		<ID>t1</ID>
		<bookproperty>
			<lang>en </lang>
			<text>string1</text>
		</bookproperty>
	</book>
	<book>
		<Name>x</Name>
		<ID>x1</ID>
		<bookproperty>
			<lang>tn</lang>
			<text>string2</text>
		</bookproperty>
	</book>
....
</Item>


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