artist's name, indicating the existence of a more elaborate copyright notice elsewhere that was still to be allowed to be placed on the mounting. Indeed, the version of the bill that was submitted to Congress in 1906, compiled by the Copyright Commission under the direction of the Librarian of Congress, Herbert Putnam, contained a provision that a special copyright symbol, the letter C inclosed within a circle, could be used instead of the word "copyright" or the abbreviation "copr.", but only for a limited category of copyrightable works, including works of art but not ordinary books or periodicals. The formulation of the 1909 Act was left unchanged when it was incorporated in 1946 as title 17 of the United States Code. A 1954 amendment to the law extended the use of the symbol to any published copyrighted work: the symbol was allowed as an alternative to "Copyright" or "Copr." in all copyright notices. US copyright notice In the United States, the copyright notice consists of: "©" or the word "Copyright" or abbreviation "Copr."; the year of first publication of the copyrighted work; and identification of the owner of the copyright, either by name, abbreviation, or other designation by which they are generally known. For example, for a work first published in 2011: The notice was once required in order to receive copyright protection in the United States, but in countries respecting the Berne convention this is no longer the case. The United States joined the Berne Convention effective March 1, 1989. Berne Convention In countries party to the Berne Convention for the Protection of Literary and Artistic Works, including the United States, a copyright notice is not required to be displayed in order for copyright to be established; rather, the creation of the work automatically establishes copyright. The United States was one of the later accedents to Berne, implementing its adherence to the treaty with the Berne Convention Implementation Act of 1988, which became effective March 1, 1989, making the notice optional. However, the copyright notice remains material in one instance: a copyright infringer cannot claim innocent infringement as a partial defense to mitigate its damages where the infringer had access to a copy of the work that bore a copyright notice. The majority of nations now belong to Berne, and thus do not require copyright notices to obtain copyright. Digital representation The character is mapped in Unicode as .