The Buenos Aires Convention is an international copyright treaty signed in Buenos Aires, Argentina, on 11 August 1910, providing mutual recognition of copyrights where the work carries a notice containing a statement of reservation of rights (Art. 3). This was commonly done with the phrase "All rights reserved" next to the copyright notice. This implementation varied as US law only required the author and year of publishing. Copyright protection under the convention is granted for the shorter of the terms of the protecting country and the source country of the work. The rather vague nature of the requirement for a statement of reservation led to the development of longer and more legalistic wordings, which have persisted despite the developments in international copyright law.