https://etd.repository.ugm.ac.id/penelitian/detail/63802001never1.0https://etd.repository.ugm.ac.id/penelitian/detail/63812001never1.0https://etd.repository.ugm.ac.id/penelitian/detail/63822001never1.0https://etd.repository.ugm.ac.id/penelitian/detail/63832001never1.0https://etd.repository.ugm.ac.id/penelitian/detail/69282001never1.0https://etd.repository.ugm.ac.id/penelitian/detail/72612001never1.0https://etd.repository.ugm.ac.id/penelitian/detail/72622001never1.0https://etd.repository.ugm.ac.id/penelitian/detail/72632001never1.0