Appropriations of the Department of Defense that are available for travel may not, without the approval of the Secretary concerned or his designee, be used for expenses incident to attendance of a member of an armed force under that department at a meeting of a technical, scientific, professional, or similar organization. ( Pub. L. 87–649 , Sept. 7, 1962 , 76 Stat. 476 , § 412; renumbered § 455, Pub. L. 112–81, div. A, title VI, § 631(d)(1) , Dec. 31, 2011 , 125 Stat. 1460 .) Historical and Revision Notes Revised section Source (U.S. Code) Source (Statutes at Large) 412 5:174a. Aug. 1, 1953, ch. 305, § 605 , 67 Stat. 349 . The words “may not . . . be used” are substituted for the words “shall not be available”. The words “on and after August 1, 1953 ” are omitted as executed. The words “Secretary concerned” are substituted for the words “Secretary of the department concerned” to conform to other sections of this revised title and to the definition in section 101(5) of this revised title. So much of the source statute as relates to civilian employees is omitted as superseded by the Act of July 7, 1958 , Pub. L. 85–507 , 72 Stat. 327 . Editorial Notes Prior Provisions Act Aug. 1, 1953 , cited as the source of this section in the Historical and Revision Notes above, is known as the Department of Defense Appropriation Act, 1954 . Similar provisions were contained in the following prior appropriation acts: July 10, 1952, ch. 630, title VI, § 606, 66 Stat. 531 . Oct. 18, 1951, ch. 512, title VI, § 606, 65 Stat. 445 . Sept. 6, 1950, ch. 896, ch. X, title VI, § 607, 64 Stat. 752 . Oct. 29, 1949, ch. 787, title VI, § 607, 63 Stat. 1018 . June 24, 1948, ch. 632, 62 Stat. 652 . July 30, 1947, ch. 357, title I, 61 Stat. 554 . July 16, 1946, ch. 583, 60 Stat. 545 . July 3, 1945, ch. 265, 59 Stat. 388 . June 28, 1944, ch. 303, 58 Stat. 577 . Amendments 2011— Pub. L. 112–81 renumbered section 412 of this title as this section.