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Copyright expiration releases works to the world

Works from 1923 have entered the public domain after a 20-year extension on copyright protections. The Penn Libraries is digitizing unique works to share.
Cover of book Vinzi by Johanna Spyri showing child sitting in a windowsill and the title page of the book reading Vinzi a story of the Swiss Alps by Johanna Spyri translation by Elisabeth P. Stork and Illustrations in color by Maria L. Kirk. Philadelphia and London J.B. Lippincott Company 1923.
The Penn Libraries is digitizing and sharing books published in 1923 that have come into the public domain. One is "Vinzi a Story of the Swiss Alps," by Johanna Spyri, author of the more-famous "Heidi." The edition is the first U.S. translation to English from German, published in Philadelphia.  

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