@book{50985,
	author = {Wolff, Edward N. and Howell, David R.},
	title = {Direct measures of labor quality and postwar productivity growth in the U.S.},
	publisher = {Universidad de Puerto Rico, Unidad de Investigaciones Económicas},
	year = {1988.},
	series = {Serie de ponencias},
	address = {Mayagüez, P.R.},
	note = {Presented at the Eighth International Conference on Input-Output Techniques in Sapporo, Japan, 28 July-2 August, 1986.}
}