(en) Josie M. Rudolphi, Shelly Campo, Fred Gerr et Diane S. Rohlman, « Social and Individual Influences on Tractor Operating Practices of Young Adult Agricultural Workers », Journal of Adolescent Health, vol. 62, no 5, , p. 605–611 (ISSN1054-139X, PMID29478719, DOI10.1016/j.jadohealth.2017.11.300)
(en) Josie M. Rudolphi, Shelly Campo, Fred Gerr et Diane S. Rohlman, « Social and Individual Influences on Tractor Operating Practices of Young Adult Agricultural Workers », Journal of Adolescent Health, vol. 62, no 5, , p. 605–611 (ISSN1054-139X, PMID29478719, DOI10.1016/j.jadohealth.2017.11.300)
(en) Josie M. Rudolphi, Shelly Campo, Fred Gerr et Diane S. Rohlman, « Social and Individual Influences on Tractor Operating Practices of Young Adult Agricultural Workers », Journal of Adolescent Health, vol. 62, no 5, , p. 605–611 (ISSN1054-139X, PMID29478719, DOI10.1016/j.jadohealth.2017.11.300)
npr.org
Laura Sydell, « DIY Tractor Repair Runs Afoul Of Copyright Law », npr.com, (consulté le ) : « And the little computer screen lets him know when something is wrong. Unfortunately, Alford isn't allowed to fix it. John Deere has a digital lock on the software that runs his tractor. And it won't give him the key. [...] The company went on to say that unqualified individuals could endanger customer safety. »
