Gaya APA

Ras, F. (2013). Preferred strategies used by Pekanbaru senior high school students to learn productive skills of English . Pekanbaru: Lembaga Penelitian Universitas Riau.

Gaya MLA

Ras, Fakhri. "Preferred strategies used by Pekanbaru senior high school students to learn productive skills of English". Pekanbaru: Lembaga Penelitian Universitas Riau, 2013. .