SOLVED. Specific Bradbury short story about literature

[Amy]

There's a story by Bradbury, but I don't remember the title or which book it's in. In it, Mars is occupied by "dead" authors, but they don't cease to exist until the last copy of one of their books on earth ceases to exist. One by one they disappear...

[Spockles]

The Exiles.

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

[Amy]

Thank you, Spockles, that's it!