[wheelinsupial]

I guess you're lucky that Cal Newport starts with blog posts and turns them into books later. This post seems to be the one that introduced deep work.

https://www.calnewport.com/blog/2012/11/21/knowledge-workers...

"Last week I introduced the deep work philosophy" in this blog post links to the one above: https://www.calnewport.com/blog/2012/11/27/some-notes-on-dee...