Gaya APA

PURYANI, ., Ristono, A. (2012). Penelitian Operasional (Ed. 1). Yogyakarta: Graha Ilmu.

Gaya MLA

PURYANI, ., Ristono, Agus. "Penelitian Operasional". Ed. 1 Yogyakarta: Graha Ilmu, 2012. Text.