Neuman, W. L. (1991). Social research methods: Qualitative and quantitative approaches. Allyn and Bacon.
Dyfyniad Arddull ChicagoNeuman, William Lawrence. Social Research Methods: Qualitative and Quantitative Approaches. Boston: Allyn and Bacon, 1991.
Dyfyniad MLANeuman, William Lawrence. Social Research Methods: Qualitative and Quantitative Approaches. Allyn and Bacon, 1991.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.