PATENT

3669. ----- [STUDIEN-UND VERWERTUNGS-G. M. B. H.]  [Gas Purification.]  Netherlands Patent 43,321, no date, Schmidt, J., Das Kohlenoxyd, Akad. Verlagsgesell., Leipzig, 1950, p. 168.

See United States Patent 2,110,241 (abs. 2793).