Good call, Mike. I found this on Mudcat Cafe:
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In the U.S., copyrights lasted for 75 years after publication, and one year’s worth of music was added to the public domain each year - until we reached 1923. Then there was a bill passed by the U.S. Congress (Sonny Bono was involved), and that bill extended copyrights up to a possible total of 120 years - but it’s hard to tell what is what. If it was published before 1923, you’re home free.
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