Concept
Version 5
Created by Boundless
The Public-Education Function of Congress
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Library of Congress
The collections of the Library of Congress include more than 32 million cataloged books and other print materials in 470 languages; more than 61 million manuscripts.
Source
Boundless vets and curates high-quality, openly licensed content from around the Internet. This particular resource used the following sources:
"Library of Congress."
http://en.wikipedia.org/wiki/Library_of_Congress%23Using_the_Library
Wikipedia
GNU FDL.