https://etd.repository.ugm.ac.id/penelitian/detail/1990912021never1.0https://etd.repository.ugm.ac.id/penelitian/detail/1991552021never1.0https://etd.repository.ugm.ac.id/penelitian/detail/1998262021never1.0https://etd.repository.ugm.ac.id/penelitian/detail/2067702021never1.0https://etd.repository.ugm.ac.id/penelitian/detail/2067832021never1.0https://etd.repository.ugm.ac.id/penelitian/detail/2067892021never1.0https://etd.repository.ugm.ac.id/penelitian/detail/2068272021never1.0