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This work is in the public domain in the United States and the source country. In most cases, this means that its copyright expired under the law of the source country and it was either published prior to January 1, 1930 or its copyright also expired under the law of the United States. Its copyright has also expired in those countries with a copyright term of life of the author plus 50 years or less.
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Note that in the countries and areas that do not apply the rule of the shorter term, this work might not be in the public domain (this especially applies in Mexico and Switzerland). The creator and year of publication are essential information and must be provided. See Wikipedia:Public domain and Wikipedia:Copyrights for more details.