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References

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Secret Service Agent Listens To Earpiece

Secret Service Code Names of 11 U.S. Presidents

American bison (Bison bison) also known as buffalo or plains buffalo on the prairie, western U.S.

What’s the Difference Between Bison and Buffalo?

Nativity Scene, Adoration of the Magi, Church of the Birth of the Virgin Mary, Montenegro

Why Is Christmas in December?

bat flying

Are Bats Really Blind?

illustration of the walking titanosaurus, Patagotitan mayorum

Titanosaurs: 8 of the World's Biggest Dinosaurs

Chinese dragon sculpture or statue.

10 Legendary Creatures from Around the World

Leonardo da Vinci (1452-1519), Italian Renaissance painter from Florence. Engraving by Cosomo Colombini (d. 1812) after a Leonardo self portrait. Ca. 1500.

10 Famous Artworks by Leonardo da Vinci

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mathematics

Learn about this topic in these articles:

Greek geometry

In mathematics: Apollonius
…IV); how to draw “normal” lines to conics (that is, lines meeting them at right angles; Book V); and the congruence and similarity of conics (Book VI).
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