Help needed with some errors and checking a docbook5 with xmllint

Hi, need help checking a docbook5 xml file.

 

When I run 

 

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xsltproc --xinclude --output Test.html /home/mepi/Downloads/docbook-xsl-1.79.2/xhtml/docbook.xsl MyBook.xml 
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I get following Error:

 

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MyBook.xml:60: namespace error : Namespace prefix xl for href on link is not defined 
       If not, see <link xl:href="" <emphasis>the  
                                                               ^ 
MyBook.xml:69: namespace error : Namespace prefix xl for href on link is not defined 
       <link xl:href="" <emphasis>th 
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What do I wrong?

                                                        ^
When I try to check my File MyBook.xml with xmllint,

 

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xmllint --relaxng /usr/share/xml/docbook5/schema/rng/5.1/docbook.rng MyBook.xml
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I get following messages:

 

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MyBook.xml:18: element info: Relax-NG validity error : Element book has extra content: info 
MyBook.xml:13: element book: Relax-NG validity error : Expecting element abstract, got book 
MyBook.xml:13: element book: Relax-NG validity error : Did not expect element book there 
MyBook.xml:13: element book: Relax-NG validity error : Expecting element audiodata, got book 
MyBook.xml:13: element book: Relax-NG validity error : Expecting element example, got book 
MyBook.xml fails to validate
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What does the messages above mean?

 

The MyBook.xml file looks like:

 

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 1  <?xml version="1.0" encoding="utf-8"?>

 2  

 3  <!DOCTYPE book [

 4		<!ENTITY % MyEntitys_ent SYSTEM "MyEntitys.ent">

 5		%MyEntitys_ent;

 6  ]>

 7

 8  <book

 9     version="5.0"

10     xmlns="http://docbook.org/ns/docbook" 

11     xmlns:xi="http://www.w3.org/2001/XInclude" 

12      xmlns:xlink="http://www.w3.org/1999/xlink" 

13      xml:lang="en"> 

14

15

16   <title>My Book</title>

17 

18    <info>

19

20      <legalnotice>

21

22        <para>

23          My Text

24        </para>

25

26      </legalnotice>

27

28      <copyright>

29        <year>2010-2012</year>

30        <holder>Mr. X and me</holder>

31      </copyright>

32

33    </info>

...

60      see <link xl:href="" <emphasis>the GNU

61      homepage</emphasis></link>.

...
211  </book>

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Thanks

Pierre