APA

Smith H. R., Library of Congress, . (2018). An overview of U.S. immigration laws regulating the admission and exclusion of aliens at the border. [Washington, D.C.]: Congressional Research Service.

Chicago

Smith Hillel R, Library of Congress, . 2018. An overview of U.S. immigration laws regulating the admission and exclusion of aliens at the border. [Washington, D.C.]: Congressional Research Service.

Harvard

Smith H. R., Library of Congress, . (2018). An overview of U.S. immigration laws regulating the admission and exclusion of aliens at the border. [Washington, D.C.]: Congressional Research Service.

MLA

Smith Hillel R, Library of Congress, . An overview of U.S. immigration laws regulating the admission and exclusion of aliens at the border. [Washington, D.C.]: Congressional Research Service. 2018.