Original description (p. 107) of “Carabelli’s cusp”, tuberculus anomalus, sometimes found on the lingual surface of the upper permanent molars. It was first illustrated on Tab. XI, Fig. 4e, and Tab. XIV, Fig. 4, of Kupfertafeln zu v. Carabelli’s Anatomie des Mundes, Vienna, 1842, and later described in Carabelli's Systematisches Handbuch der Zahnkunde, Band 2, which was published posthumously in 1844.

Digital facsimile of the 1842 atlas from Google Books at this link.