Columbia subject headings:
American literature--20th century--Periodicals.
Natural history--United States--Periodicals.
Nature--Literary collections--Periodicals.
Harvard subject headings:
American literature--20th century--Periodicals
Natural history--United States--Periodicals.
Nature--Literary collections--Periodicals.
Princeton subject headings:
American literature--20th century--Periodicals.
Natural history--United States--Periodicals.
Nature--Literary collections--Periodicals.
Periodicals.