Columbia subject headings:
Information storage and retrieval systems--Statistics, Medical--Directories.
Medical care--Information services--United States.
Medicine--United States--Statistical services--Directories.
Public health--United States--Statistical services--Directories.
Harvard subject headings:
Medicine--United States--Databases--Directories.
Medicine--United States--Statistical services--Directories.
Public health--United States--Databases--Directories.
Public health--United States--Statistical services--Directories.
Princeton subject headings:
Directories.
Medicine--United States--Databases--Directories.
Medicine--United States--Statistical services--Directories.
Public health--United States--Databases--Directories.
Public health--United States--Statistical services--Directories.