Janssen, S. (2020). The world almanac and book of facts 2021. World Almanac.
Cita Chicago Style (17a ed.)Janssen, Sarah. The World Almanac and Book of Facts 2021. New York: World Almanac, 2020.
Cita MLA (8a ed.)Janssen, Sarah. The World Almanac and Book of Facts 2021. World Almanac, 2020.
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