Sommer, R., & Sommer, B. B. (1980). A practical guide to behavioral research: Tools and techniques. Oxford University Press.
Dyfyniad Arddull ChicagoSommer, Robert, and Barbara Baker Sommer. A Practical Guide to Behavioral Research: Tools and Techniques. New York: Oxford University Press, 1980.
Dyfyniad MLASommer, Robert, and Barbara Baker Sommer. A Practical Guide to Behavioral Research: Tools and Techniques. Oxford University Press, 1980.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.