Gaya APA

Creswell, J, W., W., C, J. (s.a). Research Design: qualitative, quantitative, and mixed methods approach second edition (second edition). s.l: s.n.

Gaya MLA

Creswell, John, W.., W., Creswell, John. "Research Design: qualitative, quantitative, and mixed methods approach second edition". second edition s.l: s.n, s.a. MPK.