Limp binding
Limp binding is a bookbinding method in which the book has flexible cloth, leather, vellum, or (rarely) paper sides. When the sides of the book are made of vellum, the bookbinding method is also known as limp vellum.
The cover is made with a single piece of vellum or alternative material, folded around the textblock, the front and back covers being folded double. The quires are sewn onto cords such as alum-tawed thongs and the sewing supports would be laced into the vellum cover. The thongs would also often be used at the fore edge of the covers to create a closure or tie.