Columbia subject headings:
Cartography--Congresses.
Cartography--United States--Congresses.
Surveying--Congresses.
Surveying--United States--Congresses.
Harvard subject headings:
Cartography--Congresses
Surveying--Congresses
Surveying--United States--Congresses.
Princeton subject headings:
Cartography--Congresses.
Surveying--Congresses.
Surveying--United States--Congresses.