"Om Uhre" Kjobenhavn 1843. "Handbok om orgverket" Stockholm, printed by Isaac Marcus 1850. "Organs" J. G. Töpfer, 1866 and "Construction of a simple but mechanically complete watch" M. Grossmann, 1918.
"Om Uhre" Kjobenhavn 1843. "Handbok om orgverket" Stockholm, printed by Isaac Marcus 1850. "Organs" J. G. Töpfer, 1866 and "Construction of a simple but mechanically complete watch" M. Grossmann, 1918.