Some good insights on the earlier history of the industry at: The Supermen: The Story of Seymour Cray by Charles J. Murray (1997).
A problem that has more than two possible yes/no outputs.
Aspen Hysys Introduction by Emmanuel Oloyede (2016)
Source. Holy crap, the UI is identical to Microsoft Word with that huge top bar!!! Unlisted articles are being shown, click here to show only listed articles.