How Copyright Keeps Works Disappeared User breck, in the Intellectual Freedom Amendment subreddit, 22 Oct 2021
"How Copyright Keeps Works Disappeared", Heald 2013 User gwern, in the Gwern's Link Archive subreddit, 26 Mar 2019
Study: "This paper presents new data on how copyright seems to make [Books and Music] disappear." User T4b_, in the Technology subreddit, 10 Jul 2013
How Copyright Makes Books and Music Disappear (and How Secondary Liability Rules Help Resurrect Old Songs) User T4b_, in the Applied Digital Ethics subreddit, 10 Jul 2013