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DOAJ是一个独特而广泛的索引，收录了来自世界各地的各种开放获取期刊，由不断增长的社区推动，致力于确保每个人都能在网上免费获得高质量的内容。

ERIC is an online library of education research and information, sponsored by the Institute of Education Sciences (IES) of the U.S. Department of Education.

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