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Dear Madam/Sir,

Question.  Does anyone know if there has been any research on the value 
of xHTML and CSS validation in the peer-reviewed literature (either 
social or economic benefits)?  Note that my own pages validate (and pass 
the first two levels of WAI accessibility guidelines as well).  But 
validation still seems to be elusive to many, even for the many of the 
most prestigous Universities and For-Profit firms in the world.

It's just a question.  I can't find any literature in the IEEE or ACM 
archives on the subject, but I thought your guys/gals might know.

Thanks in advance,

Wayne