The author of this image from Switzerland is unknown
, and the image was published at least 70 years ago. It is therefore in the public domain in Switzerland by virtue of Art. 31 of the Swiss Copyright Act
Note that this applies only if a reliable source is cited to indicate that the author is not publicly known; just not knowing who the author is is not enough to qualify the image as public domain. This image may not
be in the public domain in countries other than Switzerland.