In this post, you'll find three good resources for Linux reference guides online — all available at no cost.

在这篇文中，我们要介绍3个Linux在线参考指导资源——所有都是免费的。

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It features over 1,000 journals, major reference works, online books, Current Protocols laboratory manuals, and databases as well as a suite of professional and management resources.

网站涵盖了超过1000种期刊，主要涉及工作，在线书籍，当前实验室手册协议，数据库以及一批专业人员与管理者资源。

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Basic work for the sharing of library information resources includes cooperative development of library collections, online union cataloging and online reference services.

图书馆信息资源共享的基础工作，包括合作馆藏建设、联机联合编目及在线信息咨询等。

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