Original oil and gas trade magazine vintage ad for MID-CONTINENT PETROLEUM CORPORATION of Tulsa, OK. Terre Haute, IN. Omaha, NE. Chicago, IL. Minneapolis, MN. and Waterloo, IA. Producers, Refiners, Marketers of These Famous D-X Products: D-X Lubricating Gasoline, D-X Motor Oil with Extrinol. Unique 1951 old petroleum products refining industry magazine advertisement would look sensational matted and framed. Nice graphics.