Columbia subject headings:
Great Lakes (North America)--Commerce--Periodicals.
Shipping--Great Lakes (North America)--Periodicals.
Harvard subject headings:
Great Lakes (North America)--Commerce--Periodicals.
Lake Carriers' Association--Periodicals.
Shipping--Great Lakes (North America)--Periodicals.
Princeton subject headings:
Great Lakes (North America)--Commerce--Periodicals.
Shipping--Great Lakes--Periodicals.