Gaya APA

Herpinus, S. et al (1994). New Concept English First Things First: Supplementary Written Exercises . Yogyakarta: Kanisius.

Gaya MLA

Herpinus, Simanjuntak. et al. "New Concept English First Things First: Supplementary Written Exercises". Yogyakarta: Kanisius, 1994. Text.