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 31. Undated, but probably from around 1950.
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 31. Undated, but probably from around 1950.