 In July 2008, "The Economist" magazine described Wikipedia as "a user-generated reference service" and noted that Wikipedia's "elaborate moderation rules put a limit to acrimony" generated by cyber-nationalism.Jimmy Wales, a co-founder of Wikipedia, stresses that encyclopedias of any type are not usually appropriate as primary sources, and should not be relied upon as being authoritative.Carnegie Mellon Professor Randy Pausch offered the following anecdote in his book "The Last Lecture".