Maker Johann Martin, Duitsland, Augsburg.

Literatuur: Antique Tools and Instruments, Laura Maggioni e.a., 5 Continents Editions, Milaan, 2004; Sundials at Greenwich, a Catalogue of the Sundials, Horary Quadrants and Nocturnals, Hester Higton, National Maritime Museum, Oxford, 2002; Scientifica, Kunstkammer George Laue, München, 2004.