This work is in thepublic domain in the United States because it waslegally published within the United States (or the United Nations Headquarters in New York subject to Section 7 of theUnited States Headquarters Agreement) before 1964, and copyright was not renewed.

• For Class A renewal records (books only) published between 1923 and 1963, check theStanford University Copyright Renewal Database.
• For other renewal records of publications between 1922–1950, see theUniversity of Pennsylvania copyright records.
• For all records since 1978, search theU.S. Copyright Office records.

Works published in 1931 could have had their copyright renewed in 1958 or 1959,i.e. between January 1st of the 27th year after publication or registration and December 31st of the 28th year. As this work's copyright was not renewed, it entered thepublic domain on January 1st, 1960.

The longest-living author of this work died in 1937, so this work is in thepublic domain in countries and areas where the copyright term is the author'slife plus 88 years or less. This work may be in thepublic domain in countries and areas with longer native copyright terms that apply therule of the shorter term toforeign works.