From “Methods in pulmonary physiology”, by Bertels H, Bucherl E, Hertz CW, Rodewald G, Schwab M. Translated by Workman JM. Hafner Publishing Co., 1963, page 30. Undated, but probably from the mid-1930’s.
From “Methods in pulmonary physiology”, by Bertels H, Bucherl E, Hertz CW, Rodewald G, Schwab M. Translated by Workman JM. Hafner Publishing Co., 1963, page 30. Undated, but probably from the mid-1930’s.