Archive.org - A non-profit library of millions of free books, movies, software, music, websites, and more

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Archives Hub - search archives from almost 200 institutions from England, Scotland, and Wales

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arXiv e-Print Archive - Cornell University’s arXiv.org offers open access to a wealth of e-prints in math, science, and related subjects

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Catalog of U.S. Government Publications - Catalog of U.S. Government Publications to find descriptive records for historical and current publications, with direct links where available

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Library of Congress - Access to searchable source documents, historical photos, and amazing digital collections

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