At the Mountains of Madness is a novella by horror writer H. P. Lovecraft, written in February/March 1931 and originally serialized in the February, March and April 1936 issues of Astounding Stories. The story is considered by Lovecraft scholar S. T. Joshi to represent the decisive "demythology" of the Cthulhu Mythos. — Excerpted fromAt the Mountains of Madnesson Wikipedia, the free encyclopedia.
727At the Mountains of Madness — Table of ContentsH. P. Lovecraft
The author died in 1937, so this work is also in the public domain in countries and areas where the copyright term is the author's life plus 75 years or less. This work may also be in the public domain in countries and areas with longer native copyright terms that apply the rule of the shorter term to foreign works.
Works published in 1936 would have had to renew their copyright in either 1963 or 1964, i.e. at least 27 years after it was first published / registered but not later than 31 December(31 December) in the 28th year. As it was not renewed, it entered the public domain on 1 January 1965(1 January 1965).