At head of title: United States Department of Labor. Frances Perkins, secretary. Bureau of Labor Statistics. Isador Lubin, commissioner."This study .....
At head of title: United States Department of Labor. Frances Perkins, secretary. Bureau of Labor Statistics. Isador Lubin, commissioner.
"This study ... is one of a series of surveys on labor productivity under the direction of Boris Stern made by the Bureau of Labor Statistics in cooperation with the National Research Project."--Pref.