On November 7 1973, the U.S. Congress overrode President Nixon’s veto of the war powers bill, which curbed the president’s power to commit armed forces to hostilities abroad without congressional approval.
Citation:
Richert, Lucas Paul. "Congress overrides Nixons veto on Vietnam War".
The Literary Encyclopedia. First published 01 November 2008
[http://www.litencyc.com/php/stopics.php?rec=true&UID=5699, accessed 21 May 2013.]