PATENT

3691. ----- [STUDIEN-UND VERWERTUNGS-G. M. B. H.]  [Purification of Gases in Two Steps.].  Austrian Patent 155,035, no date.  Schmidt, J., Das Kohlenoxyd, Akad. Verlagsgesell. Leipzig, 1950, p. 168.

See French Patent 797,902 (abs. 3696) and United States Patent 2,110,241 (abs. 2793).