Columbia subject headings:
Harvard subject headings:
America--Description and travel--Congresses.
Cartography--America--Congresses.
Humboldt, Alexander von, 1769-1859--Congresses.
Humboldt, Alexander von, 1769-1859--Travel--America--Congresses.
Landscape painting--America--Congresses.
Natural history--Congresses
Scientific expeditions--America--History--19th century--Congresses.
Princeton subject headings:
America--Description and travel--Congresses.
Cartography--America--Congresses.
Humboldt, Alexander von, 1769-1859--Congresses.
Humboldt, Alexander von, 1769-1859--Travel--America--Congresses.
Landscape painting--America--Congresses.
Natural history--Congresses.
Scientific expeditions--America--History--19th century--Congresses.