Gaya APA

Kim, Yoon-Soo. (2009). Why? Happy Math . Jakarta: PT. Elex Media komputindo.

Gaya Chicago

Kim, Yoon-Soo. Why? Happy Math. Jakarta: PT. Elex Media komputindo, 2009. Text.

Gaya MLA

Kim, Yoon-Soo. Why? Happy Math. Jakarta: PT. Elex Media komputindo, 2009. Text.

Gaya Turabian

Kim, Yoon-Soo. Why? Happy Math. Jakarta: PT. Elex Media komputindo, 2009. Print.