Gaya APA

randjanun, D, H, A, &, D, H. (2014). Research methodology : a step by step guide for beginners (ed.4). Los Angeles: Sage.

Gaya MLA

randjanun, Drs., H.thamrin, Abdullah, &, Drs., Helmi. "Research methodology : a step by step guide for beginners". ed.4 Los Angeles: Sage, 2014. Text.