J. D. Salinger is a well-known 20th century author, most notably of Catcher in the Rye.
He was fairly prolific, writing many stories. Do any of these stories share the same universe?
Arguably, all of Salinger's published stories share the same "universe," which is his own. That said, specific overlap in characters in currently-published works is limited to the stories and novellas that revolve around the Glass family. In publication order, they are:
These are all anthologized and widely available, except the last one, which has never been published outside of the June 19, 1965 issue of The New Yorker. (It's easy to find in a library with a decent periodicals collection, however, and it's available to current subscribers of the magazine online.)
There is also a trio of stories that were published in the Saturday Evening Post in 1944 and 1945, all of which have the same main character (Babe Gladwaller); these stories have a "false" overlap with Catcher in the Rye in that there's a character named Holden Caulfield, but it's not the same person as the main character of Catcher. None of these stories are currently in print.