@unpublished{repository34121,
           title = {HKI Buku konsep dasar antariksa untuk calon guru SD},
            note = {Unpublished},
       publisher = {Universitas Muhammadiyah Prof.DR.HAMKA},
             url = {http://repository.uhamka.ac.id/id/eprint/34121/},
          author = {Zulherman, Zulherman}
}