The EB member Urnamma had access to some sources at his university that I cannot find. Sadly he is on hiatus atm. I personally cannot condone the notion of these units as Sacred as none of the sources I have access to mention such. Granted I do not have access to Zonaras, Dio Cassius or a number of other late historians. I only have access to older, better known, sources (Polybius, Livy, Diodorus, Dionysius, etc).