Atheneum Publishers

Wikipedia: https://en.wikipedia.org/wiki/Atheneum_Books

Status:

3 Publishers Start Own Firm, PW, Mar. 23, 1959, at 36-37 (announcing the as-yet-unnamed publishing venture begun by Simon Michael Bessie (editor of Harper's trade department), Hiram Haydn (Random House's editor-in-chief), and Alfred Knopf, Jr. (vice-president of Alfred A. Knopf, Inc.)).

Atheneum Publishers: Officers, Directors, Plans, PW, May 25, 1959, at 73-74 (announcing the Atheneum name).

Hiram Haydn, WORDS & FACES (HBJ 1974), https://archive.org/details/wordsfaces00hayd/mode/2up.