This work is in the public domain because it was published in the United States between 1929 and 1963, and although there may or may not have been a copyright notice, the copyright was not renewed. For further explanation, see Commons:Hirtle chart and the copyright renewal logs. Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (70 years p.m.a.), Mainland China (50 years p.m.a., not Hong Kong or Macao), Germany (70 years p.m.a.), Mexico (100 years p.m.a.), Switzerland (70 years p.m.a.), and other countries with individual treaties.
Aquest material està en domini públic als Estats Units i als altres països on el dret d'autor s'estén per 80 anys (o menys) després de la mort de l'autor.
Cal incloure una etiqueta de domini públic als Estats Units per indicar perquè aquesta obra és en domini públic als Estats Units. Note that a few countries have copyright terms longer than 80 years: Mexico has 100 years and Jamaica has 95 years. This image may not be in the public domain in these countries, which moreover do not implement the rule of the shorter term.
Aquest fitxer conté informació addicional, probablement afegida per la càmera digital o l'escàner utilitzat per a crear-lo o digitalitzar-lo. Si s'ha modificat posteriorment, alguns detalls poden no reflectir les dades reals del fitxer modificat.