1. BP Statistical Review of World Energy, 2017. Top Coal Producers in 2016
2. Mongabay series: Indonesian coal. Nithin coca 2010
3. Chesner WH, Collins RJ, MacKay M (1998) User guidelines for waste and by-product materials in pavement construction. Publication number: FHWA-RD-97-148. FHWA, Washington DC
4. RENDY, N. M., Yani, I., & Mataram, A. (2018). Pengaruh Variasi Ukuran Partikel Filler Fly Ash Terhadap Uji Tarik Komposit Matrik Polietilena Tereftalat (Doctoral dissertation, Sriwijaya University).
5. Government Regulation (PP) No. 101, 2014. Management of hazardous wastes and toxic, Indonesia