Creswell, J. W. (2011). Research Design (3rd.). Sage.
Chicago-čujuhus (17. p.)Creswell, John W. Research Design. 3rd. New Delhi: Sage, 2011.
MLA-čujuhus (9. p.)Creswell, John W. Research Design. 3rd. Sage, 2011.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.