The source element

When a topic is based on information from another resource, details of that related resource can be stored in the source metadata element in the topic prolog section.

The source element in the topic prolog section is used to nominate the name and/or location of information from which the topic was drawn or based. It is based on the Dublin Core Metadata Initiative source property. The location of the resource is recorded in the source element's href attribute.

For example, if a topic was based on figures published in a Department of Transport report, the source element may be coded as:
<source href="">
  Australian Design Rules

When published to an HTML-based output format, the address in the href attribute of the source element are included in the Dublin Core DC.source metadata in the head section of the HTML page.