United States. Government Accountability Office. Capitol Visitor Center: Update on Status of Project's Schedule and Cost as of April 27, 2006, text, April 27, 2006; (https://digital.library.unt.edu/ark:/67531/metadc290672/m1/1/: accessed December 15, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .