This commentary contains cross references to the text:
<xref n="s6.14" ...
as formulated, these create dead links on Perseus, so future work will have to make them resolve to the Gallic War text.
http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0017%3Atext%3Dcomm%3Abook%3D2%3Achapter%3D1