Co-edited by John Hinsdale Thompson and John Malcolm Brinnin and based in Detroit, Signatures was a literary magazine of "works-to-be-published-later" written by contemporary American and international writers. Subtitled "Work in Progress," Signatures was first published in the Spring of 1936 and continued for a total of three issues, ceasing publication in 1938.

Holograph calligraphy manuscript of Philip Whalen's Three Mornings, which was published by Don Allen's Four Seasons Foundation. Inscribed by Whalen to Allen and with small printer's instructions in one corner.