https://etd.repository.ugm.ac.id/penelitian/detail/772262014never1.0https://etd.repository.ugm.ac.id/penelitian/detail/773012014never1.0https://etd.repository.ugm.ac.id/penelitian/detail/773332014never1.0https://etd.repository.ugm.ac.id/penelitian/detail/776872014never1.0https://etd.repository.ugm.ac.id/penelitian/detail/778012014never1.0https://etd.repository.ugm.ac.id/penelitian/detail/779652014never1.0https://etd.repository.ugm.ac.id/penelitian/detail/780992014never1.0https://etd.repository.ugm.ac.id/penelitian/detail/787912014never1.0