@book{18421,
	author = {Labovitz, Sanford  and Hagedorn, Robert },
	title = {Introduction to social research},
	publisher = {McGraw-Hill, },
	year = {1976},
	address = {New York : },
	edition = {2 ed.},
	note = {Contiene bibliografias, glosario e indice.Una fotocopia del original.}
}