Linking external references and citations in DITA XML is an important aspect of creating comprehensive and reliable technical documentation. DITA provides several mechanisms for accomplishing this, ensuring that external content is seamlessly integrated into your documents. One common approach is using the <xref> element to reference external sources, such as websites, documents, or articles. The <xref> element allows you to link to external content by specifying the target and its title, providing users with easy access to additional resources.

Another method for linking external references is through the <linkinfo> element, which can be added to the <xref> element. The <linkinfo> element provides metadata about the linked content, including the description, source, and other relevant information. This metadata enhances the clarity and context of the external reference, helping users understand the source’s relevance and credibility.

Example:

Here’s an example of how external references and citations can be linked in DITA XML:

<p>For more information on the topic, please refer to the <xref href="https://www.example.com/document.pdf" scope="external">example document</xref>.</p>

<p>In this case, the <xref> element links to an external PDF document located at "https://www.example.com/document.pdf." The user can click on "example document" to access the external resource.</p>

In this example, the <xref> element is used to link to an external reference, and users can easily access the linked document or source. Adding <linkinfo> elements can provide additional context about the external reference, enhancing the overall usability of the documentation.