Columbia subject headings:
Harvard subject headings:
Hydraulic engineering--Alps Region.
Hydraulic engineering--Danube River Valley.
Water-supply engineering--Alps Region.
Water-supply engineering--Danube River Valley.
Princeton subject headings:
Hydraulic engineering--Alps Region--History.
Hydraulic engineering--Austria--History.
Hydraulic engineering--Germany--History.
Water-supply engineering--Alps Region--History.
Water-supply engineering--Austria--History.
Water-supply engineering--Germany--History.