William Butler Yeats

“ Of our sad hearts, that may not live nor die.
This work is in the public domain in the United States because it was published before January 1, 1928.
The longest-living author of this work died in 1939, so this work is in the public domain in countries and areas where the copyright term is the author's life plus 83 years or less. This work may 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. ”