Doing some research on your work-in-progress? Check out the Library of Congress Research and Reference Services. You’ll want to bookmark it so you can spend quality time there.
I found it to be one of the most pleasant rabbit holes I’d ever gone down.
If you’re not familiar, I recommend starting at the Quick Links (on the far right column) with the Getting Started and Frequently Asked Questions pages.
Also bookmark-worthy:
- The Library of Congress main page, which has links to just about everything
- The LOC digital collections that are free to use and reuse
- LOC blogs (in their words: “compelling stories & fascinating facts”; they are not wrong)
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