A.聯機數據庫檢索系統(tǒng) B.光盤數據庫檢索系統(tǒng) C.網絡數據庫檢索系統(tǒng) D.以上全部
A.AD= Peking Univ* and AU=wang xuan B.AD= Peking Univ* and AU=wang x C.Peking Univ* and AU=wangxuan D.Peking Univ and AU=wang xuan