I can't remember the name of Copernicus' book (something to do with 'On The Revolution of Heavenly Bodies'). He did the final editing on his deathbed, and directed that it be published after he died.

There was also a book buried in one of the crematoria at Auschwitz. It was written by unnamed sonderkommando, and was published under the authors' suggested title Amidst A Nightmare of Crime. I've read it, but can't find a citation for it.

On a lighter note, H Beam Piper's Fuzzies And Other People was found in his attic, or cellar, or something, many years after his suicide, and was published as quickly as it could be brought to press.

Goodreads has Copernicus' book listed as On The Revolutions of Heavenly Spheres. I'd list it, but I haven't read it!

Kafka's "The Castle" will have to be voted back onto the list - an adaptation of it, not by Kafka, had gotten voted on instead.

Go Set a Watchman by Harper Lee was NOT posthumous! The book was published July 14, 2015 and she died February 19, 2016 - a solid 7 months AFTER the book was published.

Add Coretta: My Life, My Love, My Legacy by Coretta Scott King which was published January 17, 2017 (10 years after her death).

You could add it yourself. It's easy to add books to lists; at the top of the list, at the tab next to 'all votes.'

I have my doubts if the 'date of first publication' as given by GR is always correct...