Vulgar Latin

An Introduction to Vulgar Latin, by Charles Hall Grandgent. Boston, 1907.
Another copy.
Another copy.

Word Formation in the Roman Sermo Plebeius. An historical study of the development of vocabulary in vulgar and late Latin, with special reference to the Romance languages. By Frederic Taber Cooper. New York, 1895.

Observations on the Use of Certain Prepositions in Petronius, with special reference to the Roman Sermo Plebeius.

Vulgärlateinische inschriften. Herausgegeben vun Dr. Ernst Diehl. Bonn: A. Marcus und E. Weber’s Verlag, 1910.