Dairy farm labour input data obtained by mail questionaire and by field intervie
Barr, W.L.
Dairy farm labour input data obtained by mail questionaire and by field intervie - Pennsylvania 1961 - 14 p. - No. 687; Pennsylvania Agricult .
Dairy farm labour input data obtained by mail questionaire and by field intervie - Pennsylvania 1961 - 14 p. - No. 687; Pennsylvania Agricult .