"Photo Encyclopedia of U.S.S. Akron & Macon Event Covers".
This is a huge 352 pages, 8 1/2 x 11, profusely illustrated with over 2,700 photographs of Macon and Akron Zep covers. It contains market values to match each photograph as well as cachetmaker and quantity produced information. Also included is a pricing section for autographs on Macon/Akron zep covers.
In addition the Photo Encyclopedia also contains all known city and airship cancels that appear on known Macon and Akron covers.
Unique Numbering System, 352 pages, 8-1/2 x 11" format