Columbia subject headings:
Erie, Lake, Region--History.
Erie, Lake--History.
Natural history--Erie, Lake.
Pollution--Erie, Lake.
Harvard subject headings:
Erie (Lake, Region)--History.
Erie, Lake--History.
Natural history--Erie, Lake.
Pollution--Erie, Lake.
Princeton subject headings:
Erie, Lake, Region--History.
Erie, Lake--History.
Natural history--Erie, Lake.
Pollution--Erie, Lake.