Gaya APA

System benadering. (2000). Malang: Angkasa.

Gaya Chicago

System benadering. . Malang: Angkasa, 2000. Text.

Gaya MLA

System benadering. . Malang: Angkasa, 2000. Text.

Gaya Turabian

System benadering. Malang: Angkasa, 2000. Print.