Image: Sibyl Rock Control Engineering 1955

Description: Photograph of Sibyl M. Rock in the article "Sibyl Rock puts digits to work" in Control Engineering, February 1955, p. 11. Mathematician Sibyl Rock is seated, smiling, in front of an ElectroData computer. No copyright renewal. No author identified. No photographer identified.
Title: Sibyl Rock Control Engineering 1955
Credit: "Sibyl Rock puts digits to work" in Control Engineering, February 1955, p. 11.
Author: No authors indicated in original
Permission: This work is in the public domain because it was published in the United States between 1927 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 (50 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.
Usage Terms: Public domain
License: Public domain
Attribution Required?: No