You should look into your state's FIC laws (Found in Collection), in there are any.
Museum Registration Methods 5th Edition by Rebecca A. Buck and Jean Allman Gilmore
A Legal Primer on Managing Museum Collections 3rd Edition by Marie Malaro
I've been relying pretty heavily on these books since I've started at my position. They cover a lot about undocumented objects, as well as other common issues found in museums.
Best,
Shelby
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Shelby Miller
Curator/Dr. of Education and Outreach
Galena History Museum
Galena IL
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