摘要

Source

授權條款

	此作品在美國屬於公有領域，因為其是由美國政府的官員或僱員，基於其個人公務目的製作的作品，參考美國法典第17篇第1章第105條。 注意︰本模板僅適用於美國聯邦政府的原創作品，不適用於任何美國州、屬地、聯邦個體、縣、市或任何次級政府的作品。本模板也不適用於1978年以後由美國郵政署出版的郵票圖案（參看美國版權局實踐綱領第313.6(C)(1)條）。也不適用於部分美國硬幣；參看美國鑄幣局使用條款。
此作品無已知的著作權限制，亦不受所有相關和鄰接的權利限制。

https://creativecommons.org/publicdomain/mark/1.0/PDMCreative Commons Public Domain Mark 1.0falsefalse

...However, any copyright held by ACME that is still current would now be owned by CORBIS. In an attempt to determine if ACME registered any copyrights and if those copyrights were renewed, Specialists in the Prints and Photographs Division of the Library of Congress searched the Copyright Office files. It was found that only a few images were registered for copyright and those copyrights were not renewed. However, the Library’s legal office has advised the Division that photographs published with proper copyright notices between 1923-1963 may be protected if properly renewed, while works published after 1963 and unpublished photographs in the collection may be protected even if they were not registered with the Copyright Office. Additionally, researchers should be advised that determining the copyright status of photographs can be problematic because of the lack of pertinent information, and researchers often have to make calculated risk decisions concerning the appropriate use of an image when its copyright status is unknown or ambiguous.

— https://www.loc.gov/rr/print/res/220_acme.html