1959. Twentieth Edition. Unpaginated. Illustrated dust jacket over blue cloth boards. Clean pages with light tanning and mild foxing throughout. More pronounced to free endpapers and pastedowns. Binding remains firm. Boards have mild edge-wear with slight rubbing to surfaces and bumping to corners. Visible wear marks to boards. Clipped jacket. Panels and spine have light edgewear with tears and creases. Minor loss to spine and edges. Moderate tanning and wear marks to flaps, panels and spine.