User blog:Rgetar/Is it legal to upload old books scans?

There is an old book printed, say, 200, 300 or 400 years ago. There are its high-resolution scans in open access at web sites of libraries where this book is stored or, maybe, at some other web sites, say, Google Books.

Are these scans in the public domain?

Can I upload parts of these scans to Wikia?

Should I ask permission from the library or from the site?

Should I reference the library or the site?