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1Professor of Radiology, Graduate School of Medicine, University of Pennsylvania, Chairman of Committee on Cancer Control of the Philadelphia County Medical Society, Philadelphia, Pa.
1Professor of Radiology, Graduate School of Medicine, University of Pennsylvania, Chairman of Committee on Cancer Control of the Philadelphia County Medical Society, Philadelphia, Pa.
*
Preceding articles in this series can be found in the Journal as follows:— 1932, 27: 521, 612; 1933, 28: 30, 182, 246, 392 and 521.