Auxiliary Benefits of Accessible Web Design: validation errors

Hello,

My name is Fernando Gutiérrez Ferrerías and I'm the translator into 
spanish of your
document entitled *"Auxiliary Benefits of Accessible Web Design"* [1].

The spanish version was originally published in the W3C site [2], 
although there is a
newer version in my website [3] 
<http://ferguweb.tx.com.ru/w3/benefits-es.html>, being the only 
difference the addition of a Disclaimer
Note in the terms of the W3C IPR-FAQ [4].

The newer version is what appears referenced in  the list of the W3C 
Translations,
Listed by Languages and Technologies [5]

Said this, I'm writing you to inform about some validation errors [6] in 
the original
code concerning to the Benefits Matrices table.

Could you please fix the document and drop a few lines to warn me when 
it's fixed?
Then I would also fix the translated version.

Thanks in advance.
Regards,
Fernando Gutiérrez Ferrerías /
http://ferguweb.tx.com.ru//

_List of links in this message:_
[1] http://www.w3.org/WAI/bcase/benefits.html
[2] http://www.w3.org/2003/11/benefits-es.html
[3] http://ferguweb.tx.com.ru/w3/benefits-es.html
[4] http://www.w3.org/Consortium/Legal/IPR-FAQ-20000620#translate
[5] http://www.w3.org/2003/03/Translations/OverviewLang.html#es
[6] 
http://validator.w3.org/check?verbose=1&uri=http://www.w3.org/WAI/bcase/benefits.html 
<http://validator.w3.org/check?verbose=1&uri=http://www.w3.org/WAI/bcase/benefits.html>

P.S.:
The errors throwed by the validator are the following ones:

   1.

      /Line 769, column 33/: reference to non-existent ID "c1"

      |<th class="r" id="rms2" headers="*c*1">Clear Navigation</th>|

      This error can be triggered by:

          * A non-existent input, select or textarea element
          * A missing id attribute
          * A typographical error in the id attribute

      Try to check the spelling and case of the id you are referring to.

      ?
      <mailto:www-validator@w3.org?Subject=%5BVE%5D%5B183%5D%20Error%20Message%20Feedback>


   2.

      /Line 785, column 33/: reference to non-existent ID "c1"

      |<th class="r" id="rms3" headers="*c*1" height="35">Device|

      This error can be triggered by:

          * A non-existent input, select or textarea element
          * A missing id attribute
          * A typographical error in the id attribute

      Try to check the spelling and case of the id you are referring to.

      ?
      <mailto:www-validator@w3.org?Subject=%5BVE%5D%5B183%5D%20Error%20Message%20Feedback>


   3.

      /Line 957, column 13/: reference to non-existent ID "ret2"

      |<td headers="*r*et2 cte4"><a class="yes" href="#sbcn">YES</a></td>|

      This error can be triggered by:

          * A non-existent input, select or textarea element
          * A missing id attribute
          * A typographical error in the id attribute

      Try to check the spelling and case of the id you are referring to.