ZX81 (English Wikipedia)

Tebbutt (June 1981) Tebbutt, Dave (June 1981). "Sinclair ZX81". Personal Computer World. Archived from the original on 6 April 2011. Retrieved 21 June 2011.

archive.org (Global: 6^th place; English: 6^th place)

"Machine Specifications". ZX Computing (3). October 1982 – via Internet Archive.
Danton, Tim (2021). The Computers That Made Britain — The Home Computer Revolution of the 1980s. Cambridge: Raspberry Pi Press. p. 295. ISBN 9781912047857. OCLC 1428903627. "the membrane keyboard was about as joyful to type on as tapioca pudding, and it had some idiosyncrasies that only a mother could love"
Horne, David (February 1983). "Full ZX-81 Chess in 1K". Your Computer. pp. 100–102. Retrieved 5 March 2018.
CRASH (May 1985) "The Sinclair Story, part two". Crash. No. 16. May 1985. p. 127 – via Internet Archive.
Libes, Sol (September 1982). "Bytelines". BYTE. pp. 490–493. Retrieved 30 December 2024.
Sinclair User (November 1983) "ZX-81 export deal signed with China". Sinclair User. November 1983. p. 17 – via Internet Archive.
Hartnell (June–July 1981) Hartnell, Tim (June–July 1981). "Review – The Sinclair ZX81". Your Computer. pp. 12–14. Retrieved 5 January 2024.
Garrett 1983. Garrett, Billy (January 1983). "The Timex/Sinclair 1000". BYTE. Vol. 8, no. 1. pp. 364–370. Retrieved 19 October 2013 – via Internet Archive.
Bridgewater & Doyle 1998, pp. 156–157. Bridgewater, Susan; Doyle, Peter (1998). Innovation in marketing. Oxford, England: Butterworth-Heinemann. ISBN 978-0-7506-4121-0 – via Internet Archive.
Sinclair User (April 1984) "ZX81 Software Scene: Golden Oldies". Sinclair User. No. 25. April 1984. p. 37 – via Internet Archive.
Green, Wayne (November 1983). "Hot Cider". inCider. p. 6. Retrieved 7 January 2015 – via Internet Archive.
Bradbeer, Robin (March 1983). "Timex upgrades Spectrum". Sinclair User. pp. 83–84. Retrieved 28 January 2015 – via Internet Archive.

archive.today (Global: 14^th place; English: 14^th place)

Hartnell (November 1981) Hartnell, Tim (November 1981). "WH Smith brings ZX-81s to the high street". Your Computer. p. 37. Archived from the original on 2 December 2012.
Revival Studios ZX81 games

arstechnica.com (Global: 388^th place; English: 265^th place)

Machkovech, Sam (17 September 2021). "RIP Sir Clive Sinclair, creator of UK's famed ZX Spectrum gaming computer". Ars Technica. Retrieved 7 December 2022.

bbc.co.uk (Global: 8^th place; English: 10^th place)

news.bbc.co.uk

BBC News (23 April 2007) "How the Spectrum began a revolution". BBC News. 23 April 2007.
BBC News (8 August 2003) "Faces of the week". BBC News. 8 August 2003.
BBC News (4 July 2003) "Top developer's code for success". BBC News. 4 July 2003.

books.google.com (Global: 3^rd place; English: 3^rd place)

New Scientist (7 February 1980). "Sinclair's machine homes in on hobbyists". New Scientist. 7 February 1980. p. 402.^{[permanent dead link]}
Valéry 1977. Valéry, Nicholas (19 May 1977). "Spare a byte for the family". New Scientist. pp. 405–406. Retrieved 25 January 2015.
Campbell 1983. Campbell, Robert (14 July 1983). "New clothes for IT in schools". New Scientist. p. 133. Retrieved 26 January 2015.^{[permanent dead link]}
Sinclair (26 June 1986) Sinclair, Clive (26 June 1986). "Sinclair spectre". New Scientist. p. 81.^{[permanent dead link]}
Clarke (11 February 1982) Clarke, Robin (11 February 1982). "Microcomputers: No room at the inn". New Scientist. p. 390.^{[permanent dead link]}
Needle (15 March 1982) Needle, David (15 March 1982). "Times will market Sinclair computers". InfoWorld.
Wise (2 November 1981) Wise, Deborah (2 November 1981). "British company announces inexpensive computer". InfoWorld.
Peltu (30 April 1981) Peltu, Malcolm (30 April 1981). "Paperback processing – The Sinclair ZX81 personal computer". New Scientist. p. 303.^{[permanent dead link]}
Robinson, Phillip (30 May 1983). "The Timex/Sinclair 1000, a low-cost, book-size micro". InfoWorld. pp. 55–58. Retrieved 29 December 2024.
Kewney (3 May 1982) Kewney, Guy (3 May 1982). "Sinclair launches another low-cost microcomputer". InfoWorld.

computinghistory.org.uk (Global: low place; English: low place)

"Sinclair ZX81 - Computer - Computing History". www.computinghistory.org.uk. Retrieved 9 August 2023.

crashonline.org.uk (Global: low place; English: low place)

"The 14th ZX Microfair". Crash. No. 12 Christmas Special 1984/85. December 1984.

digitalspy.co.uk (Global: 277^th place; English: 196^th place)

Reynolds (28 June 2009) Reynolds, Matthew (28 June 2009). "Gaming – Interview – Rhianna Pratchett ('Overlord')". Digital Spy.

electronicsweekly.com (Global: low place; English: low place)

Manners, David (20 September 2021). "Uncle Clive". Electronics Weekly. Retrieved 6 December 2022.

fwscart.com (Global: low place; English: low place)

cronosoft.fwscart.com

"Sinclair ZX81". Cronosoft.

gamasutra.com (Global: 704^th place; English: 507^th place)

Wallis (15 February 2007) Wallis, Alistair (15 February 2007). "Playing Catch Up: Match Day's Jon Ritman". Gamasutra. Archived from the original on 24 March 2007.

highbeam.com (Global: 405^th place; English: 256^th place)

business.highbeam.com

Gillies-Jones (22 June 2000) Gillies-Jones, Ray (22 June 2000). "Remember ZX80, ZX81, ZX Spectrum". Computer Weekly. Archived from the original on 11 October 2012.

homecomputer.de (Global: low place; English: low place)

"Sinclair ZX-81 (Beocomp)". The Home Computer Museum.

ieee.org (Global: 652^nd place; English: 515^th place)

spectrum.ieee.org

Cass, Stephen (23 February 2018). "Build Your Own Altair 8800 Personal Computer". IEEE Spectrum. Retrieved 7 December 2022.

measuringworth.com (Global: 2,465^th place; English: 1,383^rd place)

"Measuring Worth (retail price index)". measuringworth.com. Retrieved 19 November 2022.

myprius.co.za (Global: low place; English: low place)

"Sinclair ZX81 Data Tapes".

news.google.com (Global: 59^th place; English: 45^th place)

"Toy-like but a best seller". The Age. 9 March 1982. p. 33. Retrieved 16 March 2014.

pcmag.com (Global: 1,060^th place; English: 700^th place)

Lendino, Jamie (15 April 2022). "45 Years Ago, Apple Kickstarted the Personal Computer Industry". PCMAG. Retrieved 7 December 2022.

retrogames.co.uk (Global: low place; English: low place)

"The 8th ZX Microfair Showguide". Retrogames. Retrieved 23 February 2014.

rwapservices.co.uk (Global: low place; English: low place)

"Sinclair ZX80 / ZX81 Forums". Archived from the original on 20 October 2009. Retrieved 12 August 2009.

rwapsoftware.co.uk (Global: low place; English: low place)

"The Sinclair ZX81". RWAP Software. Retrieved 5 March 2018.

sinclairzx.com (Global: low place; English: low place)

"Sinclair ZX81". Sinclair Research. Archived from the original on 14 December 2014. Retrieved 5 January 2011.

spong.com (Global: low place; English: low place)

Joscelyne (5 November 2009) Joscelyne, Svend (5 November 2009). "Industry Legend: Charles Cecil". Spong.

techdigest.tv (Global: low place; English: low place)

Price, Chris (17 September 2021). "Sir Clive Sinclair RIP – 10 things about the great man you may not know". Tech Digest. Retrieved 6 December 2022.

theguardian.com (Global: 12^th place; English: 11^th place)

Krotoski (3-11-2003) Krotoski, Aleks (3 November 2003). "Games in literature: Gibson explores the difference between UK and US". The Guardian.
Mackintosh (27 January 2000) Mackintosh, Hamish (27 January 2000). "Why the Discworld needs PCs". The Guardian.
Mackintosh (23 September 1999) Mackintosh, Hamish (23 September 1999). "Deep thought". The Guardian.

timexsinclair.com (Global: low place; English: low place)

"Sinclair ZX81". timexsinclair.com. Retrieved 15 March 2023.

tlienhard.com (Global: low place; English: low place)

forum.tlienhard.com

forum.tlienhard.com

web.archive.org (Global: 1^st place; English: 1^st place)

"Sinclair ZX81". Sinclair Research. Archived from the original on 14 December 2014. Retrieved 5 January 2011.
McClelland 2011. McClelland, David (18 March 2011). "How a BBC Micro shaped the course of GeekDad's life". Wired. Archived from the original on 30 December 2011.
Gillies-Jones (22 June 2000) Gillies-Jones, Ray (22 June 2000). "Remember ZX80, ZX81, ZX Spectrum". Computer Weekly. Archived from the original on 11 October 2012.
Tebbutt (June 1981) Tebbutt, Dave (June 1981). "Sinclair ZX81". Personal Computer World. Archived from the original on 6 April 2011. Retrieved 21 June 2011.
Wallis (15 February 2007) Wallis, Alistair (15 February 2007). "Playing Catch Up: Match Day's Jon Ritman". Gamasutra. Archived from the original on 24 March 2007.
"Sinclair ZX80 / ZX81 Forums". Archived from the original on 20 October 2009. Retrieved 12 August 2009.
"Siggis ZX81 web server main page". Archived from the original on 27 June 2012. Retrieved 8 June 2011.

wired.co.uk (Global: 2,053^rd place; English: 1,340^th place)

McClelland 2011. McClelland, David (18 March 2011). "How a BBC Micro shaped the course of GeekDad's life". Wired. Archived from the original on 30 December 2011.

worldcat.org (Global: 5^th place; English: 5^th place)

search.worldcat.org

Danton, Tim (2021). The Computers That Made Britain — The Home Computer Revolution of the 1980s. Cambridge: Raspberry Pi Press. p. 295. ISBN 9781912047857. OCLC 1428903627. "the membrane keyboard was about as joyful to type on as tapioca pudding, and it had some idiosyncrasies that only a mother could love"

worldofspectrum.org (Global: 8,634^th place; English: 5,821^st place)

"Send in the clones". AlchNews. No. 33. Alchemist Research. 2000.

yourcomputeronline.wordpress.com (Global: low place; English: low place)

Hartnell (November 1981) Hartnell, Tim (November 1981). "WH Smith brings ZX-81s to the high street". Your Computer. p. 37. Archived from the original on 2 December 2012.

zx81-siggi.endoftheinternet.org (Global: low place; English: low place)

"Siggis ZX81 web server main page". Archived from the original on 27 June 2012. Retrieved 8 June 2011.

ZX81 (English Wikipedia)

apj.co.uk (Global: low place; English: low place)

archive.org (Global: 6th place; English: 6th place)

archive.today (Global: 14th place; English: 14th place)

arstechnica.com (Global: 388th place; English: 265th place)

bbc.co.uk (Global: 8th place; English: 10th place)

news.bbc.co.uk

books.google.com (Global: 3rd place; English: 3rd place)

computinghistory.org.uk (Global: low place; English: low place)

crashonline.org.uk (Global: low place; English: low place)

digitalspy.co.uk (Global: 277th place; English: 196th place)

electronicsweekly.com (Global: low place; English: low place)

fwscart.com (Global: low place; English: low place)

cronosoft.fwscart.com

gamasutra.com (Global: 704th place; English: 507th place)

highbeam.com (Global: 405th place; English: 256th place)

business.highbeam.com

homecomputer.de (Global: low place; English: low place)

ieee.org (Global: 652nd place; English: 515th place)

spectrum.ieee.org

measuringworth.com (Global: 2,465th place; English: 1,383rd place)

myprius.co.za (Global: low place; English: low place)

news.google.com (Global: 59th place; English: 45th place)

pcmag.com (Global: 1,060th place; English: 700th place)

retrogames.co.uk (Global: low place; English: low place)

rwapservices.co.uk (Global: low place; English: low place)

rwapsoftware.co.uk (Global: low place; English: low place)

sinclairzx.com (Global: low place; English: low place)

spong.com (Global: low place; English: low place)

techdigest.tv (Global: low place; English: low place)

theguardian.com (Global: 12th place; English: 11th place)

timexsinclair.com (Global: low place; English: low place)

tlienhard.com (Global: low place; English: low place)

forum.tlienhard.com

web.archive.org (Global: 1st place; English: 1st place)

wired.co.uk (Global: 2,053rd place; English: 1,340th place)

worldcat.org (Global: 5th place; English: 5th place)

search.worldcat.org

worldofspectrum.org (Global: 8,634th place; English: 5,821st place)

yourcomputeronline.wordpress.com (Global: low place; English: low place)

zx81-siggi.endoftheinternet.org (Global: low place; English: low place)

archive.org (Global: 6^th place; English: 6^th place)

archive.today (Global: 14^th place; English: 14^th place)

arstechnica.com (Global: 388^th place; English: 265^th place)

bbc.co.uk (Global: 8^th place; English: 10^th place)

books.google.com (Global: 3^rd place; English: 3^rd place)

digitalspy.co.uk (Global: 277^th place; English: 196^th place)

gamasutra.com (Global: 704^th place; English: 507^th place)

highbeam.com (Global: 405^th place; English: 256^th place)

ieee.org (Global: 652^nd place; English: 515^th place)

measuringworth.com (Global: 2,465^th place; English: 1,383^rd place)

news.google.com (Global: 59^th place; English: 45^th place)

pcmag.com (Global: 1,060^th place; English: 700^th place)

theguardian.com (Global: 12^th place; English: 11^th place)

web.archive.org (Global: 1^st place; English: 1^st place)

wired.co.uk (Global: 2,053^rd place; English: 1,340^th place)

worldcat.org (Global: 5^th place; English: 5^th place)

worldofspectrum.org (Global: 8,634^th place; English: 5,821^st place)