Usulan Perbaikan Penggunaan Barang Milik Negara Sebagai Dasar (Underlying Asset) Penerbitan Surat Berharga Syariah Negara (Studi Kasus Pada Direktorat Jenderal Kekayaan Negara Kementerian Keuangan) = Improvement Recommendations of State-Owned Assets' Use as Underlying Asset for Indonesia Government Islamic Securities Issuance (Case Study on Directorate General State-Asset Management Ministry of Finance)