I didn'know that:
In the United States, as a result of successive changes in the law, works first published between 1924 and 1978 are protected for a period of 95 years after this first publication, i.e., until 2073 at the most and 2019 at the least. However, in most countries of the world, the Berne Convention applies with a protection of 50 or 70 years after the death of the author; that is to say until 2049 at the most for works by authors who died in 1978, and at least 1975 for authors who died in 1924.