In the late 80s, while checking out Brown University, S.T. Joshi found Lovecraft’s original typescripts.

Comparing them to what had been published to that point, he found the editors had made dramatic changes, often removing entire paragraphs, so they could fit in more advertising.

Working with Arkham House starting in 1985, they republished the stories based on the original typescripts.

According to the wiki, this is the “corrected sixth printing” of only 4,124 copies.

https://en.wikipedia.org/wiki/The_Dunwich_Horror_and_Others

https://en.wikipedia.org/wiki/At_the_Mountains_of_Madness_and_Other_Novels

https://en.wikipedia.org/wiki/Dagon_and_Other_Macabre_Tales

https://en.wikipedia.org/wiki/The_Horror_in_the_Museum_and_Other_Revisions

https://en.wikipedia.org/wiki/The_Watchers_Out_of_Time_and_Others

https://lovecraft.fandom.com/wiki/New_Tales_of_the_Cthulhu_Mythos