https://etd.repository.ugm.ac.id/penelitian/detail/143772000never1.0https://etd.repository.ugm.ac.id/penelitian/detail/144282000never1.0https://etd.repository.ugm.ac.id/penelitian/detail/144392000never1.0https://etd.repository.ugm.ac.id/penelitian/detail/145262000never1.0https://etd.repository.ugm.ac.id/penelitian/detail/145272000never1.0https://etd.repository.ugm.ac.id/penelitian/detail/145282000never1.0https://etd.repository.ugm.ac.id/penelitian/detail/146392000never1.0