To change a local related link into an external related link to a newly-created document, do the following:
To call up the
Change Local Related Link Dialog, choose or click the
Insert External Related Link button
on the toolbar.
To change the local related link into external, click the External Link tab.
To call up the
Create New DITA Document Dialog, click the
Create New DITA Document button
.
The Create New DITA Document Dialog will appear.
Figure 1. Create New DITA Document Dialog.

In the Create New DITA Document Dialog, do the following:
From the Template drop-down list, select a template for the new document.
In the Title field, type the title of the new document.
The Id field gets filled in automatically when you are typing the title.
In the File field, specify the name of the new document.
The new document will be saved in the directory of the current document. To specify another location for saving the new document, use the Browse button.

The new document will be created.
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From the Type drop-down list, select a type: e.g. concept, task, etc.
local
peer
external
You can also check the Close on Change checkbox, and then click the Change button.