1936 Moscow imprint

We have a mathematics book printed in Moscow in 1936 "under combined technical-scientific editorship of Peoples Commissariat ... of the USSR."

Would be grateful for any authoritative comment on whether this work is in the public domain.

A Slavic bibliographer suggests that it is not under a copyright because the Soviet Union was not party to copyright convention until much later.

Can anyone reading this list help us out?

                                        Thanks.

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        212-998-3314 (v)                Carol Hutchins
        hutchins[_at_]nyu.edu                NYU Courant Institute Library
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