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美国目录检索服务公司经营的联机情报检索系统是世界5大联机情报检索系统之一,为全美图书馆与情报中心服务,1979年又开始为奥地利、比利时、卢森堡、荷兰、葡萄牙、西班牙、瑞士与南斯拉夫等国提供服务。这个系统的检索特点是用自由词检索,次日提供打印的查找结果,检索年限一般可回溯至1966年。目前,该系统拥有下列23种来自联帮政
One of the top 5 online intelligence retrieval systems in the world is the online information retrieval system operated by the U.S. catalog search service. It serves the National Library and Information Center and began operations in 1979 for Austria, Belgium, Luxembourg, the Netherlands, Portugal, Spain, Switzerland and the United States Yugoslavia and other countries to provide services. This system is characterized by retrieval of free words, the next day to provide print search results, the search period can be traced back to 1966. At present, the system has the following 23 kinds from the joint help government