@unpublished{repository50130,
           title = {Bukti ajar SEI},
       publisher = {Universitas Muhammadiyah Prof Dr. HAMKA},
            note = {Unpublished},
             url = {http://repository.uhamka.ac.id/id/eprint/50130/},
          author = {Hamid Al Jufri, Jufri}
}