TI - GOvernment services PT - JOUR DP - 1939 TA - Journal of the American Medical Association pages = {1821}, VI - 113 IP - 20 AID - 10.1001/jama.1939.02800450043017 [doi] 4100 - http://dx.doi.org/10.1001/jama.1939.02800450043017 SO - Journal of the American Medical Association November 11, 1939 113(20):1821