John Deere 20 Series New Generation Tractors: The ultimate book on Deere and Company's ultimate tractors. Built from 1964 to 1972 John Deere's 20 series New Generation tractors were perhaps the finest built by any company. Covers the models 820,1020,1520, 2020,2520, 3020, 4000,4020,4320,4520,4620,5020,6030,WA12-17 and 8020. Gives history, production numbers, original prices, serial numbers/years and much much more. Many color photos. A must for any collector of these great tractors.