Gaya APA

S, A., Irzam, Y. (2011). Economics 2 A: for senior high school grade xi semester 1 (Cet.6). Jakarta: .

Gaya MLA

S, Alam., Irzam, Yansen. "Economics 2 A: for senior high school grade xi semester 1". Cet.6 Jakarta: , 2011. Text.