Columbia subject headings:
Electric industries--Germany--History.
Industrialists--Germany--Biography.
Siemens & Halske--History.
Siemens, Carl Friedrich von, 1872-1941.
Siemens, Wilhelm von, 1855-1919.
Harvard subject headings:
Electric industries--Germany--History.
Siemens Aktiengesellschaft.
Siemens, Carl Friedrich von, 1872-1941.
Siemens, Wilhelm von, 1855-1919.
Princeton subject headings:
Electric industries--Germany--History.
Siemens Aktiengesellschaft.
Siemens, Carl Friedrich von, 1872-1941.
Siemens, Wilhelm von, 1855-1919.