The introduction of farm machinery in its relation to the productivity of labor in the agriculture of the United States during the nineteenth century
By: by Leo Rogin.
Series: University of California
Publisher: University of California Press
Published: 1931
Place of publication: Berkeley, Calif
Number of pages: 260
Subjects: Agricultural machinery; Agriculture -- United States; Agricultural laborers -- United States; Wheat
Notes: Thesis (PH.D)-Columbia university, 1931.

Vita.

Vita.   Published also without thesis note.

Index of authors cited : p. 244-251.