Difference between revisions of "Sargon"
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* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=30052 SARGON] by Vegan, [[Computer Chess Forums|Rybka Forum]], April 08, 2015 | * [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=30052 SARGON] by Vegan, [[Computer Chess Forums|Rybka Forum]], April 08, 2015 | ||
* [http://www.hiarcs.net/forums/viewtopic.php?t=8273 Kevin. E. leavelle] by [[Fernando Villegas|Fernando]], [[Computer Chess Forums|Hiarcs Forum]], February 18, 2017 | * [http://www.hiarcs.net/forums/viewtopic.php?t=8273 Kevin. E. leavelle] by [[Fernando Villegas|Fernando]], [[Computer Chess Forums|Hiarcs Forum]], February 18, 2017 | ||
+ | ==2020 ...== | ||
+ | * [http://www.talkchess.com/forum3/viewtopic.php?f=7&t=73969 Sargon 1978 - Bringing it back to life] by [[Bill Forster]], [[CCC]], May 20, 2020 | ||
+ | * [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=74027 Sargon 1978 UCI Available] by Robert C. Maddox, [[CCC]], May 27, 2020 | ||
+ | * [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=74037 Stockfish_dev is probably stronger than Sargon 1978 v1.00] by [[Kai Laskos]], [[CCC]], May 29, 2020 » [[Stockfish]] | ||
+ | * [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=76766 Sargon Android] by mephisto, [[CCC]], March 03, 2021 » [[Android]] | ||
=External Links= | =External Links= | ||
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: [http://www.andreadrian.de/schach/sargon.asm Sargon Z80 assembly listing] by [[Dan Spracklen|Dan]] and [[Kathe Spracklen]], hosted by [[Andre Adrian]] | : [http://www.andreadrian.de/schach/sargon.asm Sargon Z80 assembly listing] by [[Dan Spracklen|Dan]] and [[Kathe Spracklen]], hosted by [[Andre Adrian]] | ||
* [http://www.mobygames.com/game-group/sargon-series Sargon series] - [https://en.wikipedia.org/wiki/MobyGames MobyGames] | * [http://www.mobygames.com/game-group/sargon-series Sargon series] - [https://en.wikipedia.org/wiki/MobyGames MobyGames] | ||
− | + | * [https://github.com/billforsternz/retro-sargon GitHub - billforsternz/retro-sargon: This is a project to bring the code from the book "Sargon a computer chess program" back to life in the modern era] by [[Bill Forster]] <ref>[http://www.talkchess.com/forum3/viewtopic.php?f=7&t=73969 Sargon 1978 - Bringing it back to life] by [[Bill Forster]], [[CCC]], May 20, 2020</ref> | |
==Sargon II== | ==Sargon II== | ||
[[Apple II]], [[Atari 8-bit]], [[Commodore VIC-20]], [[Commodore 64]], [[TRS-80]] | [[Apple II]], [[Atari 8-bit]], [[Commodore VIC-20]], [[Commodore 64]], [[TRS-80]] | ||
Line 151: | Line 156: | ||
: [http://www.spacious-mind.com/html/c64_emu_-_sargon_ii.html Commodore 64 Emulator - Computer Chess Game Collection - Sargon II Chess] from [[The Spacious Mind]] | : [http://www.spacious-mind.com/html/c64_emu_-_sargon_ii.html Commodore 64 Emulator - Computer Chess Game Collection - Sargon II Chess] from [[The Spacious Mind]] | ||
* [http://www.c64-wiki.de/index.php/Sargon_II Sargon II – C64-Wiki] (German) | * [http://www.c64-wiki.de/index.php/Sargon_II Sargon II – C64-Wiki] (German) | ||
− | |||
==Sargon III== | ==Sargon III== | ||
[[Apple II]], [[Amiga]], [[Atari 8-bit]], [[Atari ST]], [[Commodore 64]], [[Macintosh]], [[IBM PC|PC]] | [[Apple II]], [[Amiga]], [[Atari 8-bit]], [[Atari ST]], [[Commodore 64]], [[Macintosh]], [[IBM PC|PC]] | ||
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* [http://www.c64-wiki.de/index.php/Sargon_III Sargon III – C64-Wiki] (German) | * [http://www.c64-wiki.de/index.php/Sargon_III Sargon III – C64-Wiki] (German) | ||
* [https://en.wikipedia.org/wiki/Computer_Chronicles Computer Chronicles]: [http://archive.org/details/Computer1985_6 Computer Games (1985)] from the [https://en.wikipedia.org/wiki/Internet_Archive Internet Archive], "[[Kathe Spracklen#LadySargon|Lady Sargon]]" introducing Sargon III for [[Macintosh]] at 4:10 | * [https://en.wikipedia.org/wiki/Computer_Chronicles Computer Chronicles]: [http://archive.org/details/Computer1985_6 Computer Games (1985)] from the [https://en.wikipedia.org/wiki/Internet_Archive Internet Archive], "[[Kathe Spracklen#LadySargon|Lady Sargon]]" introducing Sargon III for [[Macintosh]] at 4:10 | ||
− | |||
==Sargon 4== | ==Sargon 4== | ||
[[Macintosh]], [[IBM PC|PC]] | [[Macintosh]], [[IBM PC|PC]] | ||
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* [http://www.mobygames.com/game/sargon-4 Sargon 4 for DOS (1989)] - [https://en.wikipedia.org/wiki/MobyGames MobyGames] | * [http://www.mobygames.com/game/sargon-4 Sargon 4 for DOS (1989)] - [https://en.wikipedia.org/wiki/MobyGames MobyGames] | ||
* [http://www.atarimagazines.com/startv3n9/macpconst.html Sargon IV and Printer Interface III] by David Plotkin, [http://www.atarimagazines.com/index/?issue=startv3n9 STart Vol. 3 No. 9], April 1989 | * [http://www.atarimagazines.com/startv3n9/macpconst.html Sargon IV and Printer Interface III] by David Plotkin, [http://www.atarimagazines.com/index/?issue=startv3n9 STart Vol. 3 No. 9], April 1989 | ||
− | |||
==Sargon 5== | ==Sargon 5== | ||
[[Macintosh]], [[IBM PC|PC]], [https://en.wikipedia.org/wiki/Philips_CD-i Philips CD-i] | [[Macintosh]], [[IBM PC|PC]], [https://en.wikipedia.org/wiki/Philips_CD-i Philips CD-i] | ||
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* [http://www.gamefaqs.com/pc/945809-sargon-v-world-class-chess Sargon V: World Class Chess for PC] - [https://en.wikipedia.org/wiki/GameFAQs GameFAQs] | * [http://www.gamefaqs.com/pc/945809-sargon-v-world-class-chess Sargon V: World Class Chess for PC] - [https://en.wikipedia.org/wiki/GameFAQs GameFAQs] | ||
* [http://www.gamefaqs.com/cdi/937503-sargon-chess Sargon Chess for CD-I] - [https://en.wikipedia.org/wiki/GameFAQs GameFAQs] | * [http://www.gamefaqs.com/cdi/937503-sargon-chess Sargon Chess for CD-I] - [https://en.wikipedia.org/wiki/GameFAQs GameFAQs] | ||
− | |||
==Misc== | ==Misc== | ||
* [https://en.wikipedia.org/wiki/Sargon Sargon (disambiguation) from Wikipedia] | * [https://en.wikipedia.org/wiki/Sargon Sargon (disambiguation) from Wikipedia] | ||
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[[Category:68000]] | [[Category:68000]] | ||
[[Category:8086]] | [[Category:8086]] | ||
+ | [[Category:TRS-80]] | ||
[[Category:Apple II]] | [[Category:Apple II]] | ||
[[Category:Amiga]] | [[Category:Amiga]] | ||
[[Category:Atari 8-bit]] | [[Category:Atari 8-bit]] | ||
[[Category:Atari ST]] | [[Category:Atari ST]] | ||
+ | [[Category:VIC-20]] | ||
[[Category:C64]] | [[Category:C64]] | ||
[[Category:Mac]] | [[Category:Mac]] |
Latest revision as of 10:26, 6 March 2021
Sargon,
a family of chess programs by Dan and Kathe Spracklen. They started chess programming in 1977 on a Z-80 based Wavemate Jupiter III [2] in assembly language. The first Sargon version had a 10x12 board board representation and a two ply alpha-beta search without quiescence but a SOMA like exchange evaluation [3] [4].
After first tournament successes in 1978, at The Second West Coast Computer Faire, winning with a 100% score [5], and the shared third place at ACM 1978 already with Sargon II, the Spracklens became professional computer chess programmers. They first started selling their well commented Sargon I Z-80 assembly listing as paper copy for $15 by their own [6], and then made a contract with Hayden Books to publish a book about Sargon with explanations and listing [7]. Hayden Software [8] remained primary distributor of all further Sargon software versions, even when the Spracklens worked full time for Fidelity Electronics during the 80s.
Contents
MOS Technology
Sargon I was already ported to the Apple II by Kathe Spracklen's brother, Gary Shannon [9]. Despite its lower frequency, they found the 6502 the much better processor for their program than the Z80, and soon the MOS Technology processor became the major target platform.
Sargon II
Sargon II was written for various Z-80 and 6502 based home computers, and was base for their first dedicated unit, the Chafitz ARB Sargon 2.5 [10]. After civil proceedings between manufacturer Applied Concepts [11] and their sales company Chafitz, the Spracklens began their long term collaboration with Sidney Samole and Fidelity Electronics in the 80s. Sargon II already played the ACM 1978 still with the Jupiter III, and the WMCCC 1980, where it had to compete with its dedicated relatives, winner Chess Challenger, runner up Boris Experimental, Sargon 2.5 Modular GS and Sargon 2.5 Auto RB, and became tied third with 3/5, last game losing from Challenger.
Sargon III
Sargon III was a complete rewrite, using quiescence search, and a transposition table with BCH hashing. Sargon III was ported to the 68000, to be the first third-party executable software for the Macintosh [12]. The 8086 Sargon III port for PC was done by Kevin Leavelle in 1984 [13], so that three Sargon 3 software versions played the WMCCC 1984, where the Fidelity Electronics Elite by the same authors tied for first place, the Apple II became 10th with 4/7, the Macintosh 12th with 3½/7 and the 8088 Compaq PC 17th with 2½/7. In cooperation agreement between Fidelity Electronics and Software Toolworks in 1988, an enhanced and improved Sargon III was market as Fidelity Chessmaster 2100 [14].
Photos & Games
Mike
Kathe Spracklen and Mike Johnson, Mike vs. Sargon 2, ACM 1978 [15] [16]
[Event "ACM 1978"] [Site "Washington USA"] [Date "1978.12.04"] [Round "3"] [White "Mike"] [Black "Sargon 2"] [Result "1/2-1/2"] 1.e4 e5 2.d4 Nc6 3.d5 Nb4 4.c3 Na6 5.f4 Nc5 6.fxe5 Qh4+ 7.Kd2 Nxe4+ 8.Kc2 Nf2 9.Qe1 Bc5 10.Nf3 Qh5 11.Rg1 Ne7 12.Be3 Qg6+ 13.Kc1 Bxe3+ 14.Qxe3 Ng4 15.Qd2 d6 16.Bd3 Qh5 17.Bb5+ Bd7 18.Bxd7+ Kxd7 19.exd6 cxd6 20.h3 Nf6 21.Qg5 Qxg5+ 22.Nxg5 Rhf8 23.c4 Rac8 24.Nd2 Nexd5 25.Kb1 Ne3 26.Nge4 Nxe4 27.Nxe4 Rxc4 28.Nc3 f5 29.a4 d5 30.g3 Rf6 31.Re1 d4 32.Nb5 a6 33.Nxd4 f4 34.gxf4 Rxd4 35.Rxe3 Rfxf4 36.a5 Rd1+ 37.Ka2 Ra4+ 38.Ra3 Rxa3+ 39.bxa3 Rd2+ 40.Kb3 Rd3+ 41.Kc4 Rxh3 42.Rd1+ Kc6 43.a4 Rh5 44.Kb4 Rh4+ 45.Kb3 Rh3+ 46.Kc4 Rh5 47.Kb4 Rh4+ 48.Kb3 Rh3+ 49.Kc4 Rh5 50.Kb4 Rh4+ 1/2-1/2
Awit
Dan and Kathe Spracklen from their oral history on the Sargon 2 vs Awit game, round 4, ACM 1978 [17] [18]:
I think the most exciting part for us was the last round of the tournament, when we played Tony Marsland’s program Awit. It was a 6 million dollar Amdahl computer. And we won the game. And we were just amazed. I remember, at the time, we won it. And there was a huge audience there. There was like a hundred people sitting out there, watching it, and they just all started cheering and clapping. And then we woke up the following morning to a big article in the Washington Post that says, Microcomputer Beats 6 Million Dollar Machine, or something like that.
[Event "ACM 1978"] [Site "Washington USA"] [Date "1978.12.05"] [Round "4"] [White "Sargon 2"] [Black "Awit"] [Result "1-0"] 1.e4 c5 2.d4 cxd4 3.Qxd4 Nc6 4.Qe3 Nf6 5.Nf3 e6 6.Nc3 Bb4 7.Bb5 a6 8.Bxc6 dxc6 9.Bd2 Ng4 10.Qf4 Nf6 11.O-O O-O 12.Rad1 b5 13.Be3 Qa5 14.Bd4 Bxc3 15.Bxc3 Qxa2 16.Bxf6 gxf6 17.Qxf6 Qc4 18.Qg5+ Kh8 19.Qf6+ Kg8 20.Qg5+ Kh8 21.Rd8 Rxd8 22.Qf6+ Kg8 23.Qg5+ Kf8 24.Qxd8+ Kg7 25.Qg5+ Kf8 26.Qd8+ Kg7 27.Qd4+ Qxd4 28.Nxd4 Bb7 29.Re1 Kg6 30.Re3 Rd8 31.Rd3 c5 32.Nxe6 Rxd3 33.Nf4+ Kg5 34.Nxd3 Bxe4 35.Nxc5 Bxc2 36.Nxa6 Bb3 37.Nc5 Bd5 38.g3 Bf3 39.Nb3 b4 40.Nd4 Be4 41.f3 Bb7 42.Kf2 h6 43.Ke3 Bd5 44.Nc2 b3 45.Nd4 Kg6 46.Kd3 Kh7 47.f4 Kg8 48.Kc3 Kg7 49.Nxb3 Bxb3 50.Kxb3 Kf6 51.Kc4 Ke7 52.b4 Kd7 53.Kd5 h5 54.b5 Kc7 55.Kc5 Kb7 56.b6 Kb8 57.Kc6 Kc8 58.b7+ Kb8 59.Kb6 h4 60.gxh4 f6 61.h5 f5 62.Kc6 Ka7 63.Kc7 Ka6 64.b8=Q Ka5 65.Qb3 Ka6 66.Qa4# 1-0
See also
- Chafitz ARB Sargon 2.5
- Chafitz Modular Game System
- Chess Challenger
- Fidelity Chessmaster 2100
- Sargon's 10x12 Board
- SOMA Algorithm
- Spracklens debugging with Apple II ICE
Pages with Spracklen Quotes
Publications
1978 ...
- Dan Spracklen, Kathe Spracklen (1978). SARGON: A Computer Chess Program. Hayden Bk.Co.
- Chris Morgan (1978). The Second West Coast Computer Faire. BYTE, Vol. 3, No. 7 » MCCT 1978
- Dan Spracklen, Kathe Spracklen (1978). First Steps in Computer Chess Programming. BYTE, Vol. 3, No. 10, pdf from The Computer History Museum
- Dan Spracklen, Kathe Spracklen (1978). An Exchange Evaluator for Computer Chess. BYTE, Vol. 3, No. 11
- Kathe Spracklen (1978). The Making of Sargon. Personal Computing, Vol. 2, No. 12, pp. 62
- Kathe Spracklen (1979). The Playing of Sargon. Personal Computing, Vol. 3, No. 1, pp. 70
- Harry Shershow (1979). A Little Bit is a Little Better. Personal Computing, Vol. 3, No. 4, pp. 61 » Sargon - Awit
- Harry Shershow (1979). Chafitz' Big Move in Computer Chess. Personal Computing, Vol. 3, No. 9, pp. 59 » Boris, Chafitz
- Charles Sullivan Jr. (1979). A Chess Program for the Apple. Personal Computing, Vol. 3, No. 9, pp. 60 » Apple II
1980 ...
- Lynn L. Beavers (1980). Sargon II: A Human View. Personal Computing, Vol. 4, No. 9, pp. 79
- Editor (1980). The battle of Boris 2.5 vs Sargon 2.5 Personal Computing, Vol. 4, No. 10, pp. 83 » Boris 2.5, Applied Concepts, Chafitz
- William Fink (1981). Sfinks riddles Sargon II. Personal Computing, Vol. 5, No. 3, pp. 104 » Sfinks
- John F. White (1981). Survey-Chess Games. Your Computer, August/September 1981
- John F. White (1982). Review-Chess Computers. Your Computer, March 1982
- Shawn Benn, Danny Kopec (1993). The Bratko-Kopec Test Recalibrated. ICCA Journal, Vol. 16, No. 3 » Bratko-Kopec Test
2000 ...
- Rob van Son (2003). Sargon fought until the very end!. Selective Search 106, pdf hosted by Hein Veldhuis (2016)
- Gardner Hendrie (2005). Oral History of Kathe and Dan Spracklen. pdf and Video from The Computer History Museum
- Rob van Son (2011). De Assyrische krijgsman die vaak won! (Dutch) pdf hosted by Hein Veldhuis
Forum Posts
1989
1990 ...
- Sargon V rating ("they claim") by John M. Nason, rgc, September 18, 1992
- Is Sargon IV System 7 compatible? by Bertrand Limoges, rgc, October 27, 1992
- Strength of Sargon III on Commodore 64 by Daniel Marsalone, rgc, January 08, 1993
- Sargon 4 by Michael M Gorman Jr, rgc, May 27, 1993
- Sargon by Randal Dean, rgcc, March 27, 1997
- Sargon V by parrot-head, rgcc, September 15, 1999
- Sargon V: from 486-33Mhz to Pentium 266 Mhz by Fernando Villegas, CCC, December 26, 1999
- Sargon Coming down in Flames... by Fernando Villegas, CCC, December 27, 1999
2000 ...
- OLD Sargon II and Sargon III chess programs by Osorio Meirelles, CCC, April 18, 2000
- Is Sargon V code written by Dan and Kathy Spracklen ? by Osorio Meirelles, CCC, June 23, 2000
- Help with old software - Sargon III by José Carlos, CCC, November 29, 2001
- Re: Amusing errors to Sargon 4 by Fernando Villegas, CCC, August 04, 2002
- Sargon III for the PC by Jeff White, CCC, January 18, 2003
- Sargon V by Bryan Whitby, CCC, May 12, 2003
- Old Sargon source articles by Jan Willem de Kort, CCC, June 04, 2003
2010 ...
- Re: La Máquina Preservadora. Programas de Ajedrez by Luis a, Meca Foro, May 30, 2013 (Spanish) » Macintosh
- SARGON by Vegan, Rybka Forum, April 08, 2015
- Kevin. E. leavelle by Fernando, Hiarcs Forum, February 18, 2017
2020 ...
- Sargon 1978 - Bringing it back to life by Bill Forster, CCC, May 20, 2020
- Sargon 1978 UCI Available by Robert C. Maddox, CCC, May 27, 2020
- Stockfish_dev is probably stronger than Sargon 1978 v1.00 by Kai Laskos, CCC, May 29, 2020 » Stockfish
- Sargon Android by mephisto, CCC, March 03, 2021 » Android
External Links
- Sargon (chess) from Wikipedia
- Sargon's ICGA Tournaments
- The chess games of Sargon from chessgames.com
- Classic Computer Chess - ... The programs of yesteryear by Carey, hosted by the Internet Archive [19]
- How Far We've Come: 20 Years of Personal Computing by Blake Linton Wilfong, November 05, 2000 » ACM 1981, Cray Blitz, Crafty
- Sargon – a chess program from the past from ChessBase News, June 27, 2003
- Chess For Everyone - Micros Become Masters from The Computer History Museum
- Computer Schach by Andre Adrian (German)
- Sargon Z80 assembly listing by Dan and Kathe Spracklen, hosted by Andre Adrian
- Sargon series - MobyGames
- GitHub - billforsternz/retro-sargon: This is a project to bring the code from the book "Sargon a computer chess program" back to life in the modern era by Bill Forster [20]
Sargon II
Apple II, Atari 8-bit, Commodore VIC-20, Commodore 64, TRS-80
- Sargon II for VIC-20 (1982) - MobyGames
- Sargon II for Commodore 64 (1983) - MobyGames
- Sargon II (198?) Apple II cover art - MobyGames
- Early Copy Protection on the Apple II, Fadden.com » MicroChess
- Atari 400 800 XL XE Sargon II
- How to Back Up The Sargon II Tape -and- How to Put Sargon II on Disk by R Baker, from Ira Goldklang's TRS-80 Revived Site
- Sargon II Chess - GameSpot
- Commodore 64/128 Old Computer Chess Game Collection - Sargon II from The Spacious Mind
- Sargon II – C64-Wiki (German)
Sargon III
Apple II, Amiga, Atari 8-bit, Atari ST, Commodore 64, Macintosh, PC
- Sargon III for Apple II (1983) - MobyGames
- Sargon III for DOS (1983) - MobyGames
- Sargon III for Commodore 64 (1984) - MobyGames
- Sargon III for Macintosh (1984) - MobyGames
- Atari 400 800 XL XE Sargon III
- Computer Chess by Dan and Kathe Spracklen from AtariArchives.org - archiving vintage computer books, information, and software
- Commodore 64/128 Old Computer Chess Game Collection - Sargon III from The Spacious Mind
- Sargon III – C64-Wiki (German)
- Computer Chronicles: Computer Games (1985) from the Internet Archive, "Lady Sargon" introducing Sargon III for Macintosh at 4:10
Sargon 4
- The Personal Computer Museum, Brantford, Ontario, Canada - Sargon 4
- Sargon 4 for DOS (1989) - MobyGames
- Sargon IV and Printer Interface III by David Plotkin, STart Vol. 3 No. 9, April 1989
Sargon 5
- Sargon Chess program, The Computer History Museum
- Download Chess Programs hosted by Ed Schröder
- Sargon 5: World Class Chess for DOS (1991) - MobyGames
- Sargon V: World Class Chess for PC - GameFAQs
- Sargon Chess for CD-I - GameFAQs
Misc
- Sargon (disambiguation) from Wikipedia
- Sargon the Sorcerer from Wikipedia
- Sargon of Akkad from Wikipedia
- Sargon I from Wikipedia
- Sargon II from Wikipedia
References
- ↑ Sargon (chess) from Wikipedia
- ↑ Jupiter II-1975
- ↑ Dan Spracklen and Kathe Spracklen (1978). First Steps in Computer Chess Programming Byte Publications Inc., as pdf reprint from The Computer History Museum
- ↑ Sargon Z80 assembly listing by Dan and Kathe Spracklen, hosted by Andre Adrian
- ↑ Chris Morgan (1978). The Second West Coast Computer Faire. BYTE, Vol. 3, No. 7, hosted by Modern Mechanix, Photo 4: Ira Baxter’s chess playing system display, which competed in the Microcomputer Chess Tournament at the Faire. The level of play was impressive, and the winning program, called SARGON, was a 16 K byte Z-80 assembler program written by a husband and wife team, Kathe and Dan Spracklen.
- ↑ page 25 in Gardner Hendrie (2005). Oral History of Kathe and Dan Spracklen. pdf from The Computer History Museum
- ↑ Dan Spracklen and Kathe Spracklen (1978). SARGON: A Computer Chess Program. Hayden Bk.Co. ISBN: 978-0810451551, amazon.com
- ↑ Hayden Software Co. - MobyGames
- ↑ page 30 in Gardner Hendrie (2005). Oral History of Kathe and Dan Spracklen. pdf from The Computer History Museum
- ↑ Chafitz ARB Sargon 2.5 from Schachcomputer.info Wiki
- ↑ Great Game Machine
- ↑ Gardner Hendrie (2005). Oral History of Kathe and Dan Spracklen. pdf from The Computer History Museum
- ↑ Kevin Leavelle Video Game Credits and Biography - MobyGames
- ↑ Reply by Mark Manyen in Fidelity Chessmaster 2100 from The Spacious Mind
- ↑ Chess Computers - The UK Story from Chess Computer UK by Mike Watters
- ↑ PGN Download NACCC from Computerschaak/Downloads/Games hosted by CSVN
- ↑ page 35-36 in Gardner Hendrie (2005). Oral History of Kathe and Dan Spracklen. pdf from The Computer History Museum
- ↑ see also Harry Shershow (1979). A Little Bit is a Little Better. Personal Computing, Vol. 3, No. 4, pp. 61
- ↑ Re: Old programs CHAOS and USC by Dann Corbit, CCC, July 11, 2015
- ↑ Sargon 1978 - Bringing it back to life by Bill Forster, CCC, May 20, 2020