The polar collection that Stef assembled in his later years was initiated by a gift to him of three hundred books by the American Geographical Society. By now the collection, the property of Dartmouth College, numbers some twenty-five thousand bound volumes and forty-five thousand manuscripts, pamphlets, and the like. His widow, the former Evelyn Schwartz Baird, is still its able librarian, and until the end Stef could be seen quietly at work in a corner of the stacks that hold this vast assemblage of polar information.
Despite his inherent kindness, Stef did not mince words when it came to incompetence. A case in point is his evaluation of Sir John Franklin, who led an expedition to the Canadian Arctic in the mid-nineteenth century. Its entire complement of some 129 men was lost. Franklin, he said, was "by the canons of that age noble, generous, just and brave; by any standards, however, about the least professionally competent man who ever won a secure place in history.