American agriculture, 1899-1939; a study of output, employment and productivitiy, by Harold Barger and Hans H. Landsberg. (Publications of the National Bureau of Economic Research, Inc. No. 42)
American agriculture, 1899-1939; a study of output, employment and productivitiy, by Harold Barger and Hans H. Landsberg.
(Publications of the National Bureau of Economic Research, Inc. No. 42)