反过来，这些可以通过使用统一资源定位器(Universal Resource Locator, URL)或者可移植文件格式(Portable Document Format, PDF)技术来进行实施，这些技术是更深层次上ec的可再用资源。

Those, in turn, can be implemented using Universal resource Locator (URL) or Portable Document Format (PDF) technologies that are too reusable resources of the ec, just at a finer level of detail.

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用于存储超链接，这些链接提供通过URL(统一资源定位器)对网页的单击访问或通过UNC(通用命名约定)格式的名称对文件的单击访问。

Use for storing hyperlinks, which provide single-click access to Web pages through a URL (Uniform Resource Locator) or to files through a name in UNC (universal naming convention) format.

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