Citazione Stile APA (7a Edizione)
(1991). Statistical Abstract of the United States 1991: <The> National Data Book (111. ed.). U.S. Department of Commerce.
Citazione stile Chigago Style (17a edizione)
Statistical Abstract of the United States 1991: <The> National Data Book. 111. ed. Washington: U.S. Department of Commerce, 1991.
Citatione MLA (9a ed.)
Statistical Abstract of the United States 1991: <The> National Data Book. 111. ed. U.S. Department of Commerce, 1991.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.