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The Pentagon - Wikipedia
Pentagon History: 7 Big Things to Know - U.S. Department of Defense
Pentagon | History & Features | Britannica
U.S. Department of Defense > Pentagon Tours
10 Things You Probably Didn't Know About the Pentagon
Pentagon - Location, Building Timeline, 9/11 - HISTORY
Why Is the Pentagon a Pentagon? | Smithsonian
Pentagon summary | Britannica
Historical Office > DOD History > Pentagon > History