Gaya APA

Hasibuan, S, R. (1992). English for specific purpose ; tourism I : indonesian socio-cultural life and travel (cet I). Jakarta: Dian Rakyat.

Gaya MLA

Hasibuan, Sofia, Rangkuti. "English for specific purpose ; tourism I : indonesian socio-cultural life and travel". cet I Jakarta: Dian Rakyat, 1992. BUKU.