Published on the website of German public radio channel “Deutschlandradio” on 10 May 2010
Source (German):
English translation provided by @germantoenglish

Censorship in Iran is nothing new. Today, however, censorship has reached a new dimension, according to the Iranian Writer’s Association. For the first time, publishers were summoned by security authorities in the context of the Tehran book fair. Several renowned publishing houses were barred from participating in the exhibition. According to Iranian online media, only books that were published after president Ahmadinejad took office in 2005 were accepted for the exhibition. – The Tehran book fair is the leading literature-related public and trade fair in the Middle East and Central Asia.