Gaya APA

Ningrum, N, S. (1991). Aspect and Utilization of Flay Ash With Reference to Environment Impact . : Mineral Technology Development Center Directorate General of Mines.

Gaya MLA

Ningrum, Nining, Sudini. "Aspect and Utilization of Flay Ash With Reference to Environment Impact". : Mineral Technology Development Center Directorate General of Mines, 1991. Text.