@kimlockhartga @bookstodon
Oh, the author is very correct!! Every book has an ISBN barcode on the back cover. If you open GR on your phone, you can "search"; in the search window, it offers the choice to scan the ISBN. If you click, the camera opens and you can whiz through a big stack of books, scanning them all like a grocery store clerk with your apples and bananas. Just glance to see that the book was correctly entered. After that, you can return the books to shelves and they're entered.