- “vallus”, trongCharlton T. Lewis và Charles Short (1879)A Latin Dictionary, Oxford: Clarendon Press
- “vallus”, trongCharlton T. Lewis (1891)An Elementary Latin Dictionary, New York: Harper & Brothers
- vallus tại Charles du Fresne du Cange’sGlossarium Mediæ et Infimæ Latinitatis
- “vallus”, trongHarry Thurston Peck (biên tập viên) (1898),Harper's Dictionary of Classical Antiquities, New York: Harper & Brothers
- De Vaan, Michiel (2008)Etymological Dictionary of Latin and the other Italic Languages (Leiden Indo-European Etymological Dictionary Series; 7), Leiden, Boston: Brill,→ISBN,tr.652