@unpublished{repository45210,
           title = {surat tugas pemateri workshop},
       publisher = {Universitas Muhammadiyah Prof.DR.HAMKA},
            note = {Unpublished},
          author = {Zulherman, Zulherman},
             url = {http://repository.uhamka.ac.id/id/eprint/45210/}
}