These were published by Nelson Doubleday and Company in 1962. The books bindings could be paperback or possibly some sort of vinyl with leather underneath.  The vinyl or outer layer is chipping away in some spots.  These are from a smoke-free home but smell old.  My father-in-law was very proud of his book collection and put his personal name plate inside the cover of each of the books. They are boxed in an outer slip case and come with an "Introductions and Pocket Reading Guide". See the pictures for additional details. Get your hands on this rare gem today!