1961 John Deere Double-Sided Centerfold Nebraska Tests Results #961

This is yet another phenomenal double-sided centerfold magazine ad which measures @ 13 x 20" and originates from the early Sixties, most likely 1961 or so, but the ad is not dated that I can find.  It features the results of John Deere's tractor models in the Official Nebraska Testing that is done annually. Really great colors and graphics.