 Above reference has been made to bass-baritone, modern "Verdi baritone," Donizetti, and Francophone (though it is uncertain if the editor meant that as merely a nationality or as a subtype).There are 19th-century references in the musical literature to certain baritone subtypes.These include the light and tenorish baryton-Martin, named after French singer Jean-Blaise Martin (1768/69–1837), and the deeper, more powerful Heldenbariton (today's bass-baritone) of Wagnerian opera.