@unpublished{repository51637,
           title = {Peserta Tantangan dan Peluang},
       publisher = {Universitas Muhammadiyah Prof.DR.HAMKA},
            note = {Unpublished},
             url = {http://repository.uhamka.ac.id/id/eprint/51637/},
          author = {Hajar{,} Siti, Siti}
}