In 1980, Christopher Tolkien published a collection of more fragmentary material, under the title "Unfinished Tales of Númenor and Middle-earth". In subsequent years (1983–1996), he published a large amount of the remaining unpublished materials, together with notes and extensive commentary, in a series of twelve volumes called "The History of Middle-earth". They contain unfinished, abandoned, alternative, and outright contradictory accounts, since they were always a work in progress for Tolkien and he only rarely settled on a definitive version for any of the stories. There is not complete consistency between "The Lord of the Rings" and "The Hobbit", the two most closely related works, because Tolkien never fully integrated all their traditions into each other. He commented in 1965, while editing "The Hobbit" for a third edition, that he would have preferred to rewrite the book completely because of the style of its prose.