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        <title>Advanced Programming in the Unix environment</title>
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        <title>Advanced Programming in the Unix environment</title>
        <source>www.bn.com</source>
        <price>65.95</price>
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        <title> TCP/IP Illustrated </title>
        <source>www.amazon.com</source>
        <price>65.95</price>
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    <book>
        <title> TCP/IP Illustrated </title>
        <source>www.bn.com</source>
        <price>65.95</price>
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    <book>
        <title>Data on the Web</title>
        <source>www.amazon.com</source>
        <price>34.95</price>
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    <book>
        <title>Data on the Web</title>
        <source>www.bn.com</source>
        <price>39.95</price>
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