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Summary
DescriptionWugTest.png
English: In her dissertation and subsequent journal publication, w:Jean Berko Gleason developed the wug test to demonstrate how children learn English w:morphology.
The papers were published in the US in 1958, and a facsimile of the Word article provided by its publisher does not show a copyright notice suggesting the image is in the public domain for failure to comply with copyright requirements. Even if a copyright notice were visible, searching Stanford's copyright renewal database shows that the work was never renewed and is thus in the public domain.
Other investigations into the copyright status have come to the same conclusion. Dr. Gretchen McCulloch and the team at Lingthusiasm hired a lawyer to investigate the copyright status of this image. They requested documents demonstrating copyright from Gleason in April 2020 and none were provided. On the advice of their lawyer, they maintain that no copyright was ever issued and were it issued, it was not renewed.
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.