Public domain
Washington, D.C. Mixing tapioca dextrine for postage stamp gum at the United States Bureau of Engraving and Printing
From the collection of Library of Congress. Free to download, adapt and use — no permission needed.
Credit lineWashington, D.C. Mixing tapioca dextrine for postage stamp gum at the United States Bureau of Engraving and Printing. 1938-01-01. Rothstein, Arthur. Farm Security Administration/Office of War Information Collection, Library of Congress. Public domain.