^ Hermann Haack: Geographisches Jahrbuch. Volume 1, Geographisch-Kartographische Anstalt Gotha, Justus Perthes, Gotha 1866, p. XXVI
^ Christian Noback, Friedrich Eduard Noback: Complete paperback of the coin, measure and weight relationships. Volume 1, FA Brockhaus, Leipzig 1851, p. 790