http://mccallbaldwin.com/stories/the-story-of-microsoft-and-the-three-men-who-made-it/

https://books.google.com/books?id=kiOfDAAAQBAJ&pg=PT173&lpg=PT173&dq=Rowland+Hanson&source=bl&ots=GflIl9I8tW&sig=NCYKhNnTkbd5H179Pm-Nzuo87XQ&hl=en&sa=X&ved=0ahUKEwjggvD6w9PPAhUM1oMKHSSHDVs4KBDoAQhLMAk#v=onepage&q=Rowland%20Hanson&f=false

http://www.classiccmp.org/cini/pdf/random/Microsoft-Billg-Interview.pdf

http://www.poynter.org/2014/today-in-media-history-in-1983-bill-gates-and-microsoft-introduced-windows/280131/

http://www.sambadance.com/squeegee/

http://hiconsumption.com/2014/06/rich-nerds-13-things-you-might-not-know-about-microsoft/

http://www.inc.com/magazine/19841101/8173.html

http://rollercoasters-bunker.blogspot.com/2007/07/who-really-created-windows.html

https://www.thefreelibrary.com/Over+1+Million+Patents+%26+Trademarks+Are+Filed+Each+Year+But+Few+Are…-a0158612356

http://www.inc.com/magazine/19841101/8173.html

https://www.wired.com/1999/09/people-5/