00769cam a2200229 4500 43579543 TxAuBib 19990913120000.0 ||||||s1991||||||||||||||||||||||||und|u 91003056 9780879385323 0879385324 TxAuBib Leffingwell, Randy, 1948- The American farm tractor / Randy Leffingwell. Stillwater, MN : Motorbooks International, 1991. 191 p : ill ; 27 cm. Includes bibliographical references and index. 19990913. FARM TRACTORS UNITED STATES HISTORY. FARM TRACTORS UNITED STATES PICTORIAL WORKS.