44 U.S.C. § 1719

For the purpose of more fully carrying into effect the convention concluded at Brussels on March 15, 1886 , and proclaimed by the President of the United States on January 15, 1889 , there shall be supplied to the Superintendent of Documents not to exceed one hundred and twenty-five copies each of all Government publications, including the daily and bound copies of the Congressional Record, for distribution to those foreign governments which agree, as indicated by the Library of Congress, to send to the United States similar publications of their governments for delivery to the Library of Congress. Confidential matter, blank forms, circular letters not of a public character, publications determined by their issuing department, office, or establishment to be required for official use only or for strictly administrative or operational purposes which have no public interest or educational value, and publications classified for reasons of national security shall be exempted from this requirement. The printing, binding, and distribution costs of any publications distributed in accordance with this section shall be charged to appropriations provided the Superintendent of Documents for that purpose.