But as you found, there are tons of books without isbns or barcodes, especially if you go back far enough.
But even today there can be major press runs with neither - they’re only needed if you’re selling through bookstores basically.
For example, everything here is self-published with no ISBN: https://johntreed.com/collections/all
I’ve seen small libraries that gave up and organized everything by size or by color; if it’s a browsing type library it can work decently wel.
But as you found, there are tons of books without isbns or barcodes, especially if you go back far enough.
But even today there can be major press runs with neither - they’re only needed if you’re selling through bookstores basically.
For example, everything here is self-published with no ISBN: https://johntreed.com/collections/all
I’ve seen small libraries that gave up and organized everything by size or by color; if it’s a browsing type library it can work decently wel.