1969. Revised Edition. 566 pages. No dust jacket. Red cloth. Contains black and white diagrams throughout. Pages remain bright and clear with minimal tanning and foxing. Thumb-marking present. Minimal annotations to pages throughout. Boards have mild edge-wear with slight rubbing to surfaces. Minimal bumping to corners. Moderate crushing to spine ends. White scratch to rear board. Small black marks to front board. Rubbing marks to spine and rear board. Textblock is shaky.