Leffingwell’s photographic transparencies as well as his research notes for his books: Ford Farm Tractors (1998), International
Harvester Tractors (1999), Farm Tractor Milestones (2000), California Wine Country (2002), and John Deere: A History of the
Photographer, agricultural technology historian, and author of "The American Farm Tractor" (1991), "John Deere Farm Tractors"
(1993), "Classic Farm Tractors" (1993), and "Caterpillar" (1994), among other works.
All applicable copyrights for the collection are protected under chapter 17 of the U.S. Copyright Code. Requests for permission
to publish or quote from manuscripts must be submitted in writing to the Head of Special Collections. Permission for publication
is given on behalf of the Regents of the University of California as the owner of the physical items. It is not intended to
include or imply permission of the copyright holder, which must also be obtained by the researcher.
Collection is open for research.