Prior to 1978, the following was required for copyright protection (see United States Copyright Office page 2):

"Visually Perceptible Copies The notice for visually perceptible copies should contain all three elements described below. They should appear together or in close proximity on the copies.

1 The symbol © (letter C in a circle); the word “Copyright”; or the abbreviation “Copr.”

2 The year of first publication. If the work is a derivative work or a compilation incorporating previously published material, the year date of first publication of the derivative work or compilation is sufficient. Examples of derivative works are translations or dramatizations; an example of a compilation is an anthology. The year may be omitted when a pictorial, graphic, or sculptural work, with accompanying textual matter, if any, is reproduced in or on greeting cards, postcards, stationery, jewelry, dolls, toys, or useful articles.

3 The name of the copyright owner, an abbreviation by which the name can be recognized, or a generally known alternative designation of owner.1 Example © 2007 Jane Doe.")

Carefully studying the front and back scans of this vintage image, which are included in the file history and the source link, show no evidence of #1. It was therefore never under copyright.

Dit werk bevindt zich in het publieke domein vanwege het feit dat het in de Verenigde Staten van Amerika werd gepubliceerd tussen 1929 en 1977 zonder enige copyrightvermelding. Tenzij de auteur inmiddels voldoende jaren geleden is overleden is dit werk auteursrechtelijk beschermd in rechtsgebieden die de "regel van de kortere termijn" niet toepassen op Amerikaanse werken, zoals Canada (50 p.m.a.), de Volksrepubliek China (50 p.m.a., m.u.v. Hong Kong en Macau), Duitsland (70 p.m.a.), Mexico (100 p.m.a.), Zwitserland (70 p.m.a.) en andere landen met individuele verdragen. Zie deze Engelstalige pagina voor nadere toelichting. العربية ∙ беларуская (тарашкевіца) ∙ čeština ∙ Deutsch ∙ Ελληνικά ∙ English ∙ español ∙ français ∙ Bahasa Indonesia ∙ italiano ∙ 日本語 ∙ 한국어 ∙ македонски ∙ Nederlands ∙ português ∙ русский ∙ sicilianu ∙ slovenščina ∙ ไทย ∙ Tiếng Việt ∙ 中文（简体） ∙ 中文（繁體） ∙ +/−