Columbia subject headings:
Harvard subject headings:
Electric industries--Germany--History.
Electric machinery industry--Germany--History.
Public contracts--Germany--History.
Public works--Germany--History.
Siemens & Halske--History.
Princeton subject headings:
Electric industries--Germany--History.
Electric utilities--Law and legislation--Germany--History.
Siemens & Halske A.-G.
Siemens-Schuckertwerke A.-G.