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In his early career, he concentrated on the Italic dialects, including among his published work, Der Vocalismus der oskischen Sprache (1892), The Oscan-Umbrian Verb-System (1895), and Grammar of Oscan and Umbrian, with a collection of inscriptions and a glossary (1904), and a précis of the Italic languages in Johnson's Universal Cyclopaedia.
Alternatively their language may have been Italic, akin to that of their close neighbours, the Veneti (whose language, considered part of the "West Italic" sub-branch of the Italic branch of Indo-European, was closely related to Latin).