Columbia subject headings:
Harvard subject headings:
Academic libraries--Canada--Statistics--Periodicals.
Academic libraries--United States--Statistics--Periodicals.
Medical libraries--Canada--Statistics--Periodicals.
Medical libraries--United States--Statistics--Periodicals.
Princeton subject headings:
Academic libraries--Canada--Statistics--Periodicals.
Academic libraries--United States--Statistics--Periodicals.
Medical libraries--Canada--Statistics--Periodicals.
Medical libraries--United States--Statistics--Periodicals.
Periodicals.