External periodical current constraint 外控周期电流约束

periodical reversal current 周期换向电流

current periodical 现刊

current periodical room 现期期刊室

Current periodical lending 现刊外借

Chinese current periodical 中文现刊

current periodical acceptance 现刊签收

current periodical management 现刊管理

current political periodical 时政期刊