checklink

Only a little repair.
I've noticed that in the checklink validator
http://validator.w3.org/checklink there are 2 encapsulated inputs in
labels elements without the attribute "for". 

<fieldset>
  <legend>Options</legend>
  ...
    <label><input type="radio" name="hide_type" value="all"
checked="checked"> all</label>
    <label><input type="radio" name="hide_type" value="dir"> for
directories only</label>
  ...
  </p>
</fieldset>


There are WAI guidelines that referring to this matter:

http://www.w3.org/TR/WCAG10-HTML-TECHS/#forms-labels
12.4 Associate labels explicitly with their controls. [Priority 2] 
Checkpoint 12.4 <http://www.w3.org/TR/WCAG10-TECHS/>
http://www.w3.org/TR/WCAG10-TECHS/#tech-associate-labels


The question is: "It's sufficient to encapsulate input controls in
labels, or the "for" attribute in labels are always required?"

Best Regards
Hugo Silveira da Cunha

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