update: a wall mount version https://www.printables.com/model/220245-wall-mountable-single-book-stand
A simple hook designed to fit on side of bed and fits a book of up to 30mm width. Print two of these for better stability and movable so can be adjusted for any length book.
Each hook consumes 2.49m of filament so the entire setup should be ~5m(4.97m)
The author marked this model as their own original creation.