@unpublished{ITNYREPOID4081,
          author = {Hurien Helmi},
           title = {Bukti review korespondensi:Penentuan peringkat batubara berdasarakan analisa maseral di daerah tanjung belit, kabupaten dharmasraya, provinsi sumatera barat},
       publisher = {ITNY},
             url = {https://repository.itny.ac.id/id/eprint/4081/}
}