This is a photo from the National Postal Museum website. I am using it in w:Benjamin Miller Collection, if I find a better image or permission from the website I will change the tag. ; The National Postal Museum has mentioned in an e-mail to me that they have got this image from a book which they consider to be in the public domain. The name of the book is below.
Gregory, John Goadby (1931) History of Milwaukee, Wisconsin, 3, Chicago-Milwaukee: S.J. Clarke Publishing Company, p. 409 OCLC: 832745763. See also: OCLC769704872 (other ed.; vols. 1–4?).
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.
Image from the National Postal Museum, whose is goverened by the fair use terms of the Smithsonian Institution, allows use of this image for educational or non commercial purposes. http://www.si.edu/copyright/
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