This work is in the public domain both in Portugal and in the United States because it was first published in Portugal (and not published in the U.S. within 30 days) and it was first published before 1 March 1989 without complying with U.S. copyright formalities, such as copyright notice and it is one of the following:
A photographic work, work deemed to be photographic work or work of applied art created before 1 July 1970 ( more info here);
Another type of work whose author died before 1946;
An anonymous work or a work deemed to be anonymous, or a work by a collective person whose authors were not individually identified, published or disclosed before 1946.
The author died in 1929, 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 80 years or less.
For background information, see the explanations on Non-U.S. copyrights.
As of 1 January 1996, were in the public domain in Portugal: Works whose author died before 1946; anonymous works, works deemed to be anonymous, or works by a collective person whose authors were not individually identified, first published or disclosed before 1946; photographic works, works deemed to be photographic works or works of applied art created before 1971; news articles or economic, political or religious articles, published or disclosed before 1996, provided that rights have not been specifically reserved and mentions, wherever possible, the name of the author and of the publisher, of the title of the work and other elements enabling it to be identified.