Columbia subject headings:
Natural history--Great Plains.
Natural history--Prairie Provinces.
Harvard subject headings:
Great Plains.
Natural history--Great Plains--Pictorial works.
Natural history--Great Plains.
Natural history--Pictorial works
Natural history--Prairie Provinces.
Prairies--Canada--Pictorial works.
Prairies--United States--Pictorial works.
Prairies.
Princeton subject headings:
Natural history--Great Plains.
Natural history--Prairie Provinces.
Prairie ecology.