History and Development of the 567 Series GM Locomotive Engine (1951) [pdf]

If you're into the details of railroads in Utah, and especially the really detailed details about the engines that ran on them, utahrails.net is an amazing site. Don Strack is an authoritative source of information.

Hear also: “The Roar of the 567 EMD 2 stroke Diesel Engine” https://www.youtube.com/watch?v=ciJqIxLdjyQ https://www.youtube.com/watch?v=AtE6kEzE_Rc

Wiki: https://en.wikipedia.org/wiki/EMD_567