User blog comment:DaNASCAT/Technical Update: October 19, 2015/@comment-2763-20151020094004/@comment-1398253-20151021192819

That happens a lot on message boards with automatic link parsing functions. You'll inevitably get links that read as http://tardis.wikia.com/wiki/Series_9_(Doctor_Who) instead of http://tardis.wikia.com/wiki/Series_9_(Doctor_Who)

Second link works fine, first link is "in the Zero Room", which means the page doesn't exist.