Burns, R. B. (2000). Introduction to research methods (4th ed.). Sage.
Cita Chicago (17th ed.)Burns, Robert B. Introduction to Research Methods. 4th ed. London: Sage, 2000.
Cita MLA (9th ed.)Burns, Robert B. Introduction to Research Methods. 4th ed. Sage, 2000.
Atenció: Aquestes cites poden no estar 100% correctes.