The prolog.data() annotation is used to add information to the prolog of a topic. This can be anything from a simple text tag and value to an href to content located elsewhere to a complex nested structure of data elements.
The following is an example of some text from your source document that you want to put into prolog.data().
The following is an example of what the annotation may look like when filled out.
The following is an example of the DITA output you would get from this annotation.