File:Chemical Warfare in the Twentieth Century A17232.jpg

This image is in the public domain because it is a mere mechanical scan or photocopy of a public domain original, or – from the available evidence – is so similar to such a scan or photocopy that no copyright protection can be expected to arise. The original itself is in the public domain for the following reason:

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This work created by the United Kingdom Government is in the public domain. This is because it is one of the following: It is a photograph taken prior to 1 June 1957; or It was published prior to 1974; or It is an artistic work other than a photograph or engraving (e.g. a painting) which was created prior to 1974. HMSO has declared that the expiry of Crown Copyrights applies worldwide (ref: HMSO Email Reply) More information. See also Copyright and Crown copyright artistic works. Deutsch ∙ English ∙ Español ∙ français ∙ italiano ∙ Nederlands ∙ polski ∙ português ∙ sicilianu ∙ slovenščina ∙ suomi ∙ Türkçe ∙ македонски ∙ русский ∙ українська ∙ മലയാളം ∙ 한국어 ∙ 日本語 ∙ 简体中文 ∙ 繁體中文 ∙ العربية ∙ +/−

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This tag is designed for use where there may be a need to assert that any enhancements (eg brightness, contrast, colour-matching, sharpening) are in themselves insufficiently creative to generate a new copyright. It can be used where it is unknown whether any enhancements have been made, as well as when the enhancements are clear but insufficient. For known raw unenhanced scans you can use an appropriate {{PD-old}} tag instead. For usage, see Commons:When to use the PD-scan tag.

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