Tom Christiansen, brian d foy, Larry Wall, Jon Orwant (2012). “Programming Perl: Unmatched Power for Text Processing and Scripting”, p.26, "O'Reilly Media, Inc."
"The Emperor's Old Clothes". Tony Hoare's lecture at the 1980 ACM Turing Award in Nashville, Tennessee; "Communications of the ACM", Volume 24, Issue 2, dl.acm.org. February 1981.