About Ada Lovelace

https://www.oxfordreference.com/view/10.1093/oi/authority.20110803100116333

https://archives.lib.duke.edu/catalog/lovelaceada

Ada’s Notes on Luigi Menabrea’s Notes 

https://repository.ou.edu/uuid/6235e086-c11a-56f6-b50d-1b1f5aaa3f5e#page/3/mode/2up

Wikipedia diagram:

https://en.wikipedia.org/wiki/Ada_Lovelace#/media/File:Diagram_for_the_computation_of_Bernoulli_numbers.jpg

About Charles Babbage

https://cse.umn.edu/cbi/who-was-charles-babbage

Charles Babbage’s Difference Engine

https://www.britannica.com/technology/Difference-Engine

Charle’s Babbage’s Analytical Engine

https://www.computerhistory.org/babbage/engines/

Computer History Museum

https://computerhistory.org/

Other

https://web.stanford.edu/dept/HPS/riskin/computers/boehner-dorie.htm

https://www.bl.uk/collection-items/letter-from-ada-lovelace-to-charles-babbage

Contention

http://ed-thelen.org/comp-hist/CBC-Ch-02.pdf