APA (7th ed.) Citation

Youngseon, C., & Wildana, I. (2011). Why?: Light and Sound / Cahaya dan Suara. PT Elex Media Komputindo.

Chicago Style (17th ed.) Citation

Youngseon, Cho, and Iwan Wildana. Why?: Light and Sound / Cahaya Dan Suara. PT Elex Media Komputindo, 2011.

MLA (8th ed.) Citation

Youngseon, Cho, and Iwan Wildana. Why?: Light and Sound / Cahaya Dan Suara. PT Elex Media Komputindo, 2011.

Warning: These citations may not always be 100% accurate.