https://etd.repository.ugm.ac.id/penelitian/detail/555182012never1.0https://etd.repository.ugm.ac.id/penelitian/detail/574182012never1.0https://etd.repository.ugm.ac.id/penelitian/detail/575272012never1.0https://etd.repository.ugm.ac.id/penelitian/detail/575282012never1.0https://etd.repository.ugm.ac.id/penelitian/detail/575392012never1.0https://etd.repository.ugm.ac.id/penelitian/detail/576032012never1.0https://etd.repository.ugm.ac.id/penelitian/detail/580272012never1.0