keyword: United States -- Discovery and exploration – 0 free books.
These books do not seem to be included in the Directory of Open Access Books.
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The copyright owner has dedicated the material to the public domain by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law. You can copy, modify, distribute and perform the work, even for commercial purposes, all without asking permission.
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