APA (7th ed.) Citation

N, E. N., & Youngseon, C. (2015). Why?: Rock & Mineral. PT Elex Media Komputindo.

Chicago Style (17th ed.) Citation

N, Endah Nawang, and Cho Youngseon. Why?: Rock & Mineral. PT Elex Media Komputindo, 2015.

MLA (8th ed.) Citation

N, Endah Nawang, and Cho Youngseon. Why?: Rock & Mineral. PT Elex Media Komputindo, 2015.

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