See Isabella Herb, “Ethylene: Notes Taken from the Clinical Records,” in Anesthesia and Analgesia (December, 1923), pp. 210, 231–232; Herb, “Further Clinical Experiments with Ethylene-Oxygen Anesthesia,” Anesthesia and Analgesia (December, 1927), pp. 258–262; A.B. Luckhardt and J.B. Carter, “Physiologic Effects of Ethylene: A New Gas Anesthetic,” Journal of the American Medical Association, vol. 80 (January–June 1923), pp. 765–770.