Cita APA (7th ed.)
(2001). The world almanac and book of facts (ed.). World Almanac books.
Cita Chicago (17th ed.)
The World Almanac and Book of Facts. ed. New Jersey: World Almanac books, 2001.
Cita MLA (9th ed.)
The World Almanac and Book of Facts. ed. World Almanac books, 2001.
Atenció: Aquestes cites poden no estar 100% correctes.