?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adissertation&rft.aulast=Refki&rft.au=Refki%2C+Refki&rft.aufirst=Refki&rft.inst=Universitas+Negeri+padang&rft.date=July+2017&rft.degree=Bachelor%2FSkripsi&rft.title=Perencanaan+Penambangan+Jangka+Menengah+(Quarterly+Plan+)+Limestone+Bukit+Tajarang+PT.+Semen+Padang