* [[https://www.pinwiki.com/wiki/index.php/Williams_System_3_-_7#Problems_and_Fixes|Williams System 3 - 7]]
  * [[http://www.pinrepair.com/sys37/index2.htm#factory|Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part Two]]
  * [[https://sites.google.com/site/swaveseypinball/|Swavesey Pinball Weekend]]
  * [[https://www.pinballinfo.com/community/threads/was-solved-now-back-again-kicker-switch-issue-gorgar.52788/|Pinball info]]
  * [[https://pinballnirvana.com/forums/threads/firepower-ii-williams-1983-solenoid-fuse-blowing.11559/|Pinball Nirvana]]
  * [[https://www.ipdb.org/files/317/Williams_1980_Blackout_Manual_with_paginated_schematics.pdf|Blackout Schematics]]
  * [[https://www.youtube.com/watch?v=Nv5X1QuvvfM&t=519s|Williams system3-6 score display problems]]
  * [[https://rec.games.pinball.narkive.com/COpSJp71/tech-williams-system-6-blackout-goes-crazy#|Williams System 6 BLACKOUT goes crazy]]
  * [[https://www.pinwiki.com/wiki/index.php?title=Leon_Borre_Williams_System_3-7_Driver_Board_Repair&oldid=9930|Leon Borre Williams System 3-7 Driver Board Repair]]
  * 
  * [[https://retroarcadespecialists.co.uk|Retro Arcade Specialists UK LTD]]