Apollinari(u)s, Sidonius. Letter to Riothamus. Fifth Century AD (AD 470/472/474):

Dalton, Ormonde Maddock, tr. The Letters of Sidonius, In Two Volumes (Volume I), pp.xxviii, xxxvi, xxxvii, 76. Oxford: Clarendon Press, 1915.
https://ia802901.us.archive.org/25/items/lettersofsidoniu01sido/lettersofsidoniu01sido.pdf

[Dalton, Ormonde Maddock, tr. The Letters of Sidonius, In Two Volumes (Volume II) Oxford: Clarendon Press, 1915.
https://ia802905.us.archive.org/14/items/lettersofsidoniu02sido/lettersofsidoniu02sido.pdf]