Lewis & Short

Auser, ĕris (Ausar, Rutil. Itin. 1, 566), m., = Αὐσαρ (Strabo), a tributary stream of the river Arno, in Etruria, near Lucca, now Serchio, Plin. 3, 5, 8, § 50; cf. Mann. Ital. I. p. 350.