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I'm a hedgehog, not an egg!
This image reveals an Easter egg when the hedgehog is clicked or tapped. Another Easter egg can be found when a mouse pointer is hovered over it.[1]

An Easter egg is an intentional inside joke, a hidden message or image, or a secret feature of a work (often found in a computer program, video game, or DVD/Blu-ray Disc menu screen). The name is used to evoke the idea of a traditional Easter egg hunt.[2] The term was coined to describe a hidden message in the Atari video game Adventure that led Atari to encourage further hidden messages in later games, treating them as Easter eggs for players to find.[3]



The use of the term "Easter egg" to describe secret features originates from the 1979 video game Adventure for the Atari 2600 game console, programmed by employee Warren Robinett. At the time, Atari would not include programmers' names in the game credits, fearing that competitors would attempt to steal away their employees. Robinett, who disagreed with his supervisor over the lack of acknowledgment as well as other issues, secretly inserted the message "Created by Warren Robinett" which would only appear if a player moved their avatar over a specific pixel (the "Gray Dot") during a certain part of the game. Robinett had not told anyone at Atari about this by the time he left the company. Shortly after his departure, the Gray Dot and his message were exposed by a player who told Atari about their discovery. Atari's management initially wanted to release the game again after removing the message, but it would have been a costly effort. Steve Wright, the Director of Software Development of the Atari Consumer Division, suggested that they keep the message and encourage future games to include such messages, describing them as Easter eggs for consumers to find.[4][5][6][7]

In video gamesEdit

In addition to Robinett's name in Adventure (1979), there are many other instances where this Easter egg idea has been implemented. The first text adventure game, Colossal Cave Adventure (1976), which Adventure was fashioned from, included a few secret words including "xyzzy" that enabled the player to move between two points in the game world quickly.[8] In 2004, an Easter egg was found in Video Whizball (1978), a game for the Fairchild Channel F system, displaying programmer Bradley Reid-Selth's surname.[2] According to research by Ed Fries, the first known Easter egg in an arcade game came from Starship 1 (1977), programmed by Ron Milner; although, its existence wasn't published until 2017. By triggering the cabinet's controls in the right order, the player could get the message "Hi Ron!" displayed to them on the screen. Fries described it as "the earliest arcade game yet known that clearly meets the definition of an Easter egg" but suggested that, as more than one hundred arcade games predate Starship 1, earlier Easter eggs may still be undiscovered.[9][10] Fries noted that some Atari arcade cabinets were resold under the Kee Games label and included changes on the hardware that would make the game appear different from Atari. Anti-Aircraft II (1975) included a means to modify the circuit board to make the airplanes in the game appear as alien UFOs, which Fries surmised would have been for a Kee Games' release, but argued if this is a true Easter egg since it requires hardware modification.[10]

Since Adventure, there has been a long history of video game developers placing Easter eggs in their games.[11]:19 Most Easter eggs are intentional, where the intent was to communicate with the player or as a way of getting even with management for a slight. Easter eggs in video games have taken a variety of forms, from purely ornamental screens to aesthetic enhancements that change some element of the game during play; such as, the Easter egg included in the original Age of Empires (1997) game that changes catapult projectiles from stones to cows.[11]:19

More elaborate Easter eggs include secret levels and developers rooms, fully functional, hidden areas of the game. Developers rooms often include inside jokes from the fandom or development team and differ from a debug room in that they are specifically intended for the player to find. Some games even include hidden minigames as Easter eggs. In the LucasArts game Day of the Tentacle (1993), the original Maniac Mansion (1987) game can be played in its full version by using a home computer in a character's room.[12][13]

Other Easter eggs originated unintentionally. The Konami Code, a type of cheat code, became an intentional Easter egg in most games, but originated from Konami's Gradius (1985) for the Nintendo Entertainment System. The programmer, Kazuhisa Hashimoto, created the code as a means to rapidly debug the game by giving the player's avatar additional health and powers to easily traverse the game. These types of codes are normally removed from the game before it is shipped but, in the case of Gradius, Hashimoto forgot to remove it and the code was soon discovered by players. Its popularity inspired Konami to reuse the code and purposely retain it for many of its future games as an Easter egg.[2][12][14]

Technical issues may also create unintentional Easter eggs. Jon Burt, founder of Traveller's Tales, announced that many seemingly apparent Easter eggs of their Sega Genesis games were a result of introducing programming tricks to get around some of the difficulty they had in getting Sega's strict certification for their games, catching any exceptions during execution to bring the game back to a usable state as to pass certification. For example, hitting the side of the Sonic 3D Blast (1996) cartridge while it was slotted in the console would bring the game back to the Level Select screen, which Burt explained was the default exception handling for any unidentified processor error such as when connectivity between the cartridge and the console's microprocessor was temporarily lost.[15]

In computingEdit


Asking Google Maps for walking directions between fictional locations from Lord of the Rings produced this "Easter egg" response, quoting a character's warning from the story.[16]

In computer software, Easter eggs are secret responses that occur as a result of an undocumented set of commands. The results can vary from a simple printed message or image to a page of programmer credits or a small video game hidden inside an otherwise serious piece of software.

In the TOPS-10 operating system (for the DEC PDP-10 computer), the make command is used to invoke the TECO editor to create a file. if given the file name argument love, so that the command reads make love, it will pause and respond not war? before creating the file.[17] This same behavior occurred on the RSTS/E operating system, where TECO will provide this response.[citation needed] Other Unix operating systems respond to "why" with "why not" (a reference to The Prisoner in Berkeley Unix 1977).[citation needed]

Some versions of the DEC OpenVMS operating system have concealed exit status codes including a reference to the Monty Python Dirty Hungarian Phrasebook skit; "exit %xb70" returns the message "%SYSTEM-W-FISH, my hovercraft is full of eels" while "exit %x34b4" returns a reference to an early Internet meme: "%SYSTEM-F-GAMEOVER, All your base are belong to us".[18]

Many personal computers have much more elaborate eggs hidden in ROM, including lists of the developers' names, political exhortations, snatches of music, or images of the entire development team. Easter eggs in the 1997 version of Microsoft Office include a hidden flight simulator in Microsoft Excel and a pinball game in Microsoft Word.[19][20] As of 2005, Microsoft no longer allows undocumented code (including Easter eggs) in their products, fearing that unexpected and unknown 'surprises' would erode their clients' trust in the safety of the software.[citation needed]

The Debian operating system's package tool apt-get has an Easter egg involving an ASCII cow when variants on apt-get moo are typed into the shell.[21][22]

An Easter egg is found on all Microsoft Windows operating systems before XP. In the 3D Text screen saver, entering the text "volcano" would display the names of all the volcanoes in the United States. Microsoft removed this Easter egg in XP but added others.[23] Microsoft Excel 95 contained a hidden action game similar to Doom (1993) called The Hall of Tortured Souls.[24]

Easter eggs in Google Android OS

The Google search engine famously contains many Easter eggs, given to the user in response to certain search queries. For example, Google Maps once responded to a request for directions from New York City to Tokyo by telling the user to kayak across the Pacific Ocean.[25]

Steve Jobs banned Easter eggs from Apple products upon his return to the company.[26] The first Easter egg to appear after his death was in a 2012 update to the Mac App Store for OS X Mountain Lion, in which downloaded apps were temporarily timestamped as "January 24, 1984", the date of the sales launch of the original Macintosh.[26]


The Macintosh SE has an easter egg hidden in the ROMs: four images of the engineering team.

While computer-related Easter eggs are often found in software, occasionally they exist in hardware or firmware of certain devices. On some home computers the BIOS ROM contains Easter eggs. Notable examples include some errant 1993 AMI BIOS that on November 13, 1993, proceeded to play "Happy Birthday" via the PC speaker repeatedly instead of booting,[27] as well as several early Apple Macintosh models that had pictures of the development team in the ROM. These Mac Easter eggs were well-publicized in the Macintosh press at the time[28] along with the means to access them and were later recovered by an NYC Resistor team, a hacker collective, through elaborate reverse engineering.[29][30] Similarly, the Radio Shack Color Computer 3's ROM contains code which displays what looks like three Microware developers on a Ctrl+Alt+Reset keypress sequence—a hard reset which discards any information currently in RAM.[31]

Several oscilloscopes contain Easter eggs. One example is the HP 54600B, known to have a Tetris (1984) clone,[32] and the HP 54622D contains an imitation of the Asteroids (1979) game named Rocks.[33] Another is the Tektronix 1755A Vector and Waveform Monitor which displays swimming fish when Remote>Software version is selected on the CONFIG menu.[34]

In the second and third hardware revision of the Minolta Dynax/Maxxum/Alpha 9 SLR camera, including all SSM/ADI upgraded cameras, an undocumented button sequence can be utilized to reconfigure the camera to behave like the Dynax/Maxxum/Alpha 9Ti and subsequently invoke support for the limited model's extra functions also in the black model.[citation needed]

The Commodore Amiga 1000 computer includes the signatures of the design and development team embossed on the inside of the case, including Jay Miner and the paw print of his dog Mitchy.[35] The Commodore Amiga models 500, 600, and 1200 each feature Easter eggs in the form of song titles by The B-52's as white printing on the motherboards. The 500 says "B52/Rock Lobster", the 600 says "June Bug", and the 1200 says "Channel Z".[36] The Amiga OS software contains hidden messages.[37][38]

Many integrated circuit (chip) designers have included hidden graphics elements termed chip art, including images, phrases, developer initials, logos, and more. This artwork, like the rest of the chip, is reproduced in each copy by lithography and etching. These are visible only when the chip package is opened and examined under magnification.[citation needed] The 1984 CVAX microchip implementation of the MicroVAX CPU contained in its etchings the Russian phrase in the Cyrillic alphabet "VAX: When you care enough to steal the very best", placed there because, "knowing that some CVAX's would end up in the USSR, the team wanted the Russians to know that we were thinking of them".[citation needed]


American comic book artists are known to include hidden messages in their art.[39] Examples include:

In 2017, comic book artist Ardian Syaf caused an outcry with the Easter eggs he placed into his art for X-Men Gold #1.
  • In a reprint of classic Captain America comics, a production artist drew a penis on Bucky Barnes.[40]
  • In 2000, Al Milgrom inserted a message into a Universe X: Spidey #1 insulting his previous boss, Marvel Editor in Chief Bob Harras, following Harras' termination from Marvel Comics. On Page 28, panel 3, the spines of books on a bookshelf in the background read, "HARRAS HA HA, HE'S GONE, GOOD RIDDANCE TO BAD RUBBISH HE WAS A NASTY S.O.B." The message was spotted after the book was printed but before it went on sale; although, 4,000 preview copies were distributed to retailers as part of a "First Look" deal, and are considered rare. The copies that were printed for consumers were destroyed, and Milgrom was "apparently fired and allegedly (and quietly) re-hired several weeks later".[40][41][42]
  • Ethan Van Sciver hid the word "sex" into the background of nearly every page of New X-Men #118 (November 2001).[40][43] Van Sciver subsequently stated that he hid the word throughout the book because he was annoyed with Marvel at the time for reasons he cannot remember, and he thought it would be fun to engage in some mischief with his work.[citation needed]
  • Indonesian artist Ardian Syaf is known to engage in the practice of hiding Easter egg references to political figures in the backgrounds of his artwork. In Batgirl (Vol 4) #9 (July 2012), for example, Syaf included a storefront sign that referenced the President of Indonesia, Joko Widodo, although the text that accompanies the image of Widodo is covered by a caption.[40][44] In 2017 he caused an outcry by placing Easter egg references to the November 2016 Jakarta protests into the pages of X-Men Gold #1, which were perceived by readers to be anti-Semitic and anti-Christian. Though Syaf acknowledged the political nature of the messages,[40][45] he stated that they were not intended to express any anti-Semitic nor anti-Christian sentiment on his part.[46] In response to these Easter eggs, Marvel terminated their contract with Syaf.[47]


Home mediaEdit

Easter eggs are found on film, DVDs, and Blu-rays Discs, often as deleted scenes or bonus features.[48][49][50][51][unreliable source] Klinger states that their presence is "another signifier of artistry in the world of DVD supplements."[49] According to Berardinelli and Ebert, most DVDs do not contain them and most examples are "inconsequential", but a very few, such as one found on the Memento DVD release, are "worth the effort to seek out".[50]

The TV series Doctor Who has an episode using Easter eggs as a major part of the plot; the episode in question even has an Easter egg on the chapter selection for that episode on the disc release, showing the full in-episode Easter egg.[citation needed]

Broadcast mediaEdit

Unlike DVDs and computer games, broadcast radio and television programs contain no executable code. Easter eggs may still appear in the content itself, such as a hidden Mickey in a Disney film or a real telephone number instead of a 555 fictitious telephone number.[original research?] A 2014 Super Bowl advertisement was leaked online in which a lady gives a man a real telephone number which the advertiser had hidden as a marketing ploy; the first caller to the number received a pair of tickets to the game.[52] The 1980s animated series She-Ra: Princess of Power featured a character, Loo-Kee, who typically was hidden in a single screenshot within an episode, marking his only appearance in that episode. After the end of the episode, the screenshot would be shown again and the character would challenge viewers to locate him, before revealing his hiding place.[53][unreliable source]

Security concernsEdit

Security author Michel E. Kabay discussed security concerns in 2000, saying that software quality assurance requires that all code be tested, but it is not known if Easter eggs are tested. He said that because they tend to be held as programming secrets from the rest of the product testing process, a "logic bomb" could also bypass testing. Kabay asserts that this undermined the Trusted Computing Base, a paradigm of trustworthy hardware and software, in place since the 1980s, and is of concern wherever personal or confidential information is stored, which may then be vulnerable to damage or manipulation.[54][not in citation given] Microsoft created some of the largest and most elaborate Easter eggs, such as those in Microsoft Office.[55] In 2005, Larry Osterman of Microsoft acknowledged Microsoft Easter eggs, and his involvement in development of one, but described them as "irresponsible", and wrote that the company's Operating System division "has a 'no Easter Eggs' policy" as part of its Trustworthy Computing initiative.[citation needed]

Douglas W. Jones said in 2006, "some Easter eggs may be intentional tools used to detect illegal copying, others are clearly examples of unauthorized functionality that has slipped through the quality-control tests at the vendor". While hidden Easter eggs themselves are harmless, it may be possible for malware to be hidden in similar ways in voting machines or other computers.[56]

Netscape Navigator contributor Jamie Zawinski stated in an interview in 1998 that harmless Easter eggs impose a negligible burden on shipped software, and serve the important purpose of helping productivity, by keeping programmers happy.[57]

In popular cultureEdit

  • A core plot element of the Doctor Who episode "Blink" is the existence of video Easter egg across a number of DVDs that leads to solving the protagonists' dilemma.
  • The novel Ready Player One and its film adaption involve the discovery of Easter eggs in several video games in a virtual reality setting, in particular highlighting the Adventure Easter egg.

See alsoEdit


  1. ^ "Zwei Kaninchen und ein Igel" ("Two rabbits and a hedgehog") by Carl Oswald Rostosky.
  2. ^ a b c Wolf, Mark J.P. (2012). Encyclopedia of Video Games: The Culture, Technology, and Art of Gaming. Santa Barbara, California: Greenwood. p. 177. ISBN 9780313379369. 
  3. ^ Yarwood, Jack (March 27, 2016). "Easter Eggs: The Hidden Secrets of Videogames". Paste. Retrieved November 23, 2017. 
  4. ^ "Play Atari Adventure". IGN. Retrieved 4 November 2017. 
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  6. ^ Salen, Katie; Zimmerman, Eric (2005). The Game Design Reader: A Rules of the Play Anthology. Cambridge, Massachusetts: MIT Press. pp. 690–713. ISBN 0262195364. 
  7. ^ "Letter to Atari" (PDF). 2600 Connections. Wayback Machine. August 4, 1980. Archived from the original (PDF) on October 13, 2016. Retrieved September 2, 2016. 
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  11. ^ a b Consalvo, Mia (2007). Cheating: Gaining Advantage in Videogames. Cambridge, Massachusetts: MIT Press. ISBN 9780262033657. 
  12. ^ a b Björk, Staffan; Holopainen, Jussi (2005). Patterns In Game Design (1st ed.). Hingham, Massachusetts: Charles River Media. p. 235. ISBN 9781584503545. Retrieved 25 January 2013. 
  13. ^ "Optical Information Systems Update/library & Information Center Applications". CD-ROM World. Meckler Publishing. 9 (1-5). February 1994. Retrieved 4 November 2017. The best Easter egg of all is the entire Maniac Mansion game, which appears on a computer in Doctor Fred's mansion. Users can play the original game in its entirety. 
  14. ^ Garmon, Jay (5 March 2007). "Geek Trivia: The cheat goes on". TechRepublic. Retrieved 16 April 2008. 
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  21. ^ Grant, Rickford with; Bull, Phil (2010). Ubuntu for Non-Geeks: A Pain-Free, Get-Things-Done Guide (4th ed.). San Francisco: No Starch. p. 168. ISBN 9781593272579. Retrieved 25 January 2013. 
  22. ^ "apt-". Archived from the original on February 27, 2009. [dead link]
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  25. ^ Firth, Niall (29 October 2010). "How do I get to China? Jet ski! Google Maps joke gives users unorthodox instructions for crossing the Pacific". Daily Mail. Retrieved 29 October 2010. 
  26. ^ a b Diaz, Jesus (26 July 2012). "The Easter Eggs Are Back in OS X—And This One Is Insanely Great". Gizmodo. Retrieved 4 November 2017. 
  27. ^ "Happy Birthday Description". F-Secure Labs. Retrieved 3 July 2012. 
  28. ^ Kendig, Brain (1994). "Macintosh/Newton Easter Egg List". Retrieved 4 November 2017. 
  29. ^ hudson (21 August 2012). "Ghosts in the ROM". NYC Resistor. Archived from the original on 17 February 2015. Retrieved 23 March 2015. 
  30. ^ Tirosh, Udi (22 August 2012). "Photographs Of Apple Team Found In 25 Years Old Macintosh SE". DIY Photography. Archived from the original on 26 February 2013. Retrieved 4 November 2017. 
  31. ^ "The World of 68' Micros, The - Vol. 5 Number 6". 5 (6). FARNA Systems. May 1998: 5. Retrieved 4 November 2017. 
  32. ^ kcbhiw (24 July 2001). "HP 54600B Oscilloscope Easter Egg - Tetris Within Oscilloscope". The Easter Egg Archive. Retrieved 4 November 2017. 
  33. ^ TonyK (24 April 2002). "HP 54622D Easter Egg - HP Asteroids". The Easter Egg Archive. Retrieved 11 March 2015. 
  34. ^ Pavel (8 April 2000). "Tektronix 1751 Digital Video Osciloscope / Vectorscope Easter Egg - Fishes Swimming on Screen". The Easter Egg Archive. Retrieved 4 November 2017. 
  35. ^ Corrigan, Patricia (2007). Bringing Science to Life: A Guide from the Saint Louis Science. St. Louis, Missouri: Reedy Press. p. 69. ISBN 9781933370163. 
  36. ^ "(title needed)". Compute. Small System Service. 12 (6–9). 1990. 
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  40. ^ a b c d e Johnston, Rich (8 April 2017). "Marvel Artist Ardian Syaf Hid Antisemitic And Anti-Christian Messages In This Week's X-Men Comic". Bleeding Cool. Retrieved 4 November 2017. 
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  43. ^ Cronin, Brian (19 July 2011). "Comic Book Easter Eggs - New "Se"X-Men #118 Edition!". Comic Book Resources. Retrieved 4 November 2017. 
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  46. ^ "Buni Yani Questioned Again in Cyber Harassment Case". Jakarta Globe. January 2017. Retrieved 4 November 2017. 
  47. ^ Brown, Tracy (11 April 2017). "Today in Entertainment: Inside Disney's Pandora; Fyre Fest's apology; and 'Hamilton' ticket details". Los Angeles Times. Retrieved 4 November 2017. 
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  57. ^ Spolsky, Joel (2004). Joel on Software. Berkeley, California: Apress. p. 280. ISBN 9781590593899. Retrieved 4 November 2017. 

External linksEdit