A.N.Sadhu & Amarjit Singh. (1980). Research Methodology in Social sciences.
Dyfyniad Arddull ChicagoA.N.Sadhu & Amarjit Singh. Research Methodology in Social Sciences. Himalaya Publishing House,Mumbai, 1980.
Dyfyniad MLAA.N.Sadhu & Amarjit Singh. Research Methodology in Social Sciences. 1980.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.