1961. 6th Edition, Revised. 191 pages. Pictorial dust jacket over green cloth. Binding remains firm. Pages are lightly tanned throughout. Previous owner's inscription to front pastedown. Ink staining to text block edges. Boards have light shelf-wear with corner bumping. Slight crushing to spine ends. Water staining to front board. Unclipped jacket has moderate edgewear with chips, tears, and creasing. Light tanning to spine and edges. Water staining to spine. Wear marks overall.