Vaughan-Nichols, Steven J. "Opinion: The top 10 operating system stinkersArchivado el 23 de julio de 2014 en Wayback Machine." in Computerworld, April 9, 2009: "But after more than 25 years in development, GNU remains incomplete: Its kernel, Hurd, has never really made it out of the starting blocks.... Almost no one has actually been able to use the OS; it's really more a set of ideas than an operating system."
Hillesley, Richard. "GNU HURD: Altered visions and lost promise", June 30, 2010. See especially page 3: "Nearly twenty years later the HURD has still to reach maturity, and has never achieved production quality."... "Some of us are still wishing and hoping for the real deal, a GNU operating system with a GNU kernel."
«GNU's Not Unix». Thefreedictionary.com. Consultado el 22 de septiembre de 2012.
ubuntu.com
help.ubuntu.com
«What is GNU/Linux?». Help.ubuntu.com. Archivado desde el original el 16 de marzo de 2013. Consultado el 22 de septiembre de 2012.
web.archive.org
Vaughan-Nichols, Steven J. "Opinion: The top 10 operating system stinkersArchivado el 23 de julio de 2014 en Wayback Machine." in Computerworld, April 9, 2009: "But after more than 25 years in development, GNU remains incomplete: Its kernel, Hurd, has never really made it out of the starting blocks.... Almost no one has actually been able to use the OS; it's really more a set of ideas than an operating system."
«What is GNU/Linux?». Help.ubuntu.com. Archivado desde el original el 16 de marzo de 2013. Consultado el 22 de septiembre de 2012.
