But if you prefer more in-depth information:
https://en.wikipedia.org/wiki/Burroughs_large_systems
http://www.cs.virginia.edu/brochure/images/manuals/b5000/bro...
http://www.smecc.org/The%20Architecture%20%20of%20the%20Burr...
https://news.ycombinator.com/item?id=6988535
https://www.youtube.com/watch?v=K3q5n1mR9iM
But if you prefer more in-depth information:
https://en.wikipedia.org/wiki/Burroughs_large_systems
http://www.cs.virginia.edu/brochure/images/manuals/b5000/bro...
http://www.smecc.org/The%20Architecture%20%20of%20the%20Burr...
https://news.ycombinator.com/item?id=6988535
https://www.youtube.com/watch?v=K3q5n1mR9iM