Refer here for how to create a version set.
Once a Version Set has been created you can add extra documents to it:
1. Select the documents you want to add1. To view a list of Version sets on your projects expand the Publication Space Menu item.
2. Click on the Version set button in the toolbar (see above) or Basket tools drop down (see above)
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Version Sets option.
3. A list of Version Sets will open in the center pane.
4. Click anywhere on the row of the Version Set you would like to
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view.
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