Babbie, Earl
The practice of social research - 4th ed. - Belmont, Calif. : Wadsworth, 1986 - 577
SOCIAL SCIENCES--RESEARCH
H62 / B322P 1986
The practice of social research - 4th ed. - Belmont, Calif. : Wadsworth, 1986 - 577
SOCIAL SCIENCES--RESEARCH
H62 / B322P 1986