The Public Domain Review's Guide to Finding Interesting Public Domain Works Online
This handy guide outlines dozens of sources for public domain and Creative Commons content from all over the web. We recommend this guide as a great starting point for a public domain content search. The list is maintained by the Open Knowledge Foundation's Public Domain Review website.
The Library of Congress
A fantastic great resource not only for historical photographs, but also for maps, lithographs, broadsheets, manuscripts and miscellaneous ephemera – basically, those “other documents” that can add dimension and historical context to your anthology. Be sure to check the Rights Advisory for a piece of content before including it (this is normally included in the “About This Item” tab that accompanies each item). Also, items in special collections may only be usable under certain conditions.
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