Inaccessible links on Wikipedia

[From Matti Kolu (2014.01.13.2045 CET)]

The Wikipedia article on Perceptual Control Theory contains some
broken links. Three out of the four links under the External
links/Articles heading are currently either broken or not accessible
for the public:

   Web articles on PCT***
   PCT for the Beginner by William T. Powers (2007)
   The Dispute Over Control theory by William T. Powers (1993)***
   Demonstrations of perceptual control by Gary Cziko (2006)***

The first link returns a 404, while the last two are hosted on with the permissions set in such a way that the documents
are not accessible to the general public.

I have fixed the two audio interview links. (They were still referring
to rather than