Columbia subject headings:
North America--Antiquities--Congresses.
Paleo-Indians--North America--Congresses.
Paleoecology--North America--Congresses.
Paleontology--Pleistocene--Congresses.
Harvard subject headings:
North America--Antiquities--Congresses.
Paleo-Indians--North America--Congresses.
Paleoecology--North America--Congresses.
Paleontology--Pleistocene--Congresses.
Princeton subject headings:
Glacial epoch--North America.
Indian chronology.
Paleo-Indians--North America--Chronology.
Paleoclimatology--North America.
Paleoecology--North America.