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Summary
DescriptionOrson Welles as Harry Lime laying on a staircase.jpg
English: Orson Welles portraying Harry Like in The Third Man, loosely holding a Webley Mk IV Duty Model while climbing a staircase.
Date
Source
Getty Images
Author
Unknown authorUnknown author
I found this image off of a stock photo site but it is unlikely to be under copyright. The tags on the photograph call it a news photo meaning it was certainly published around 1949 when the movie came out and the website indicates it was taken, and being a promotional photo it is extremely unlikely the copyright was renewed.
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.