Gaya APA

Barlow, C., Kian, W, T. (1988). The North Sumatran Regional Economy growth with Unbalanced Develovment . Singapore: Insitute of Southeast Asian Studies.

Gaya MLA

Barlow, Colin., Kian, Wil, Thee. "The North Sumatran Regional Economy growth with Unbalanced Develovment". Singapore: Insitute of Southeast Asian Studies, 1988. Text.