Why would I need a book holder, you ask?

Because I realised how troublesome it is to hold the book when I'm reading on the desk [Also: see post title]. I don't even know if that would help..! I think it would be more beneficial for hardcover books. The book holder I have in mind is something often associated with cookbooks. There's also the small type for thumb but I would still have to hold the book using my hand.

I've already found some good candidates but I'm going to sleep on it... for maybe a week. I might change my mind few days later.