Divide electronic reference resources into various types such as database, electronic reference book, search engine, electronic journal from micro-angle and describe the types in detail.

从微观角度将电子参考源分为数据库、传统工具书的电子版、搜索引擎、电子期刊等类型，并对各类型电子参考源作详细论述。

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Divide electronic reference resources into various types such as database, electronic reference book, search engine, electronic journal from micro-angle and describe the types in detail.

从微观角度将电子参考源分为数据库、传统工具书的电子版、搜索引擎、电子期刊等类型，并对各类型电子参考源作详细论述。

youdao