@unpublished{repository7387,
            note = {Unpublished},
           title = {Teach. Sec. Math. in English},
       publisher = {Universitas Muhammadiyah Prof DR HAMKA},
             url = {http://repository.uhamka.ac.id/id/eprint/7387/},
          author = {Subhan Ajiz, Awalludin}
}