File:Hoff - La Chimie physique et ses applications - fig. 2.png

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	The author died in 1911, so this work is in the public domain in its country of origin and other countries and areas where the copyright term is the author's life plus 100 years or fewer. This work is in the public domain in the United States because it was published (or registered with the U.S. Copyright Office) before January 1, 1929.
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https://creativecommons.org/publicdomain/mark/1.0/PDMCreative Commons Public Domain Mark 1.0falsefalse

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