Allen & Unwin, The first three books in on was in fact the 1968 paperback edition. The first 3-1 hardback was 1969 printed with rice paper to make it thinner.  The 1968 is one of the more iconic editions and a must have for any collection.  The covers are genrally fine like tis one, few still have the red title on the spine as they fade sitting on the shelf.  This is as nice as they come these days.