Re:January 1, 2023 is Public Domain Day: Works from 1927 are...
by tmtvl on Tuesday December 20, 2022 @09:35PM
(#34076026)
It may have been published without a copyright notice? As it was published between 1927 and 1977, that would explain why it's in the public domain: https://commons.m.wikimedia.org/wiki/Commons:Hirtle_chart
[1]https://en.m.wikipedia.org/wiki/2_B_R_0_2_B