Columbia subject headings:
Harvard subject headings:
Mammals, Fossil.
Paleontology, Stratigraphic.
Paleontology--South America
Paleontology--Tertiary
Princeton subject headings:
Geology, Stratigraphic--Tertiary.
Geology--South America.
Mammals, Fossil--South America.
Paleontology--South America.
Paleontology--Tertiary.