Columbia subject headings:
Executive privilege (Government information)--United States--History--Sources.
National security--Law and legislation--United States--History--Sources.
Nixon, Richard M. (Richard Milhous), 1913-1994--Impeachment--Sources.
Watergate Affair, 1972-1974--Sources.
Harvard subject headings:
Executive privilege (Government information)--United States--History--Sources.
National security--Law and legislation--United States--History--Sources.
Nixon, Richard M. (Richard Milhous), 1913-1994--Impeachment--Sources.
Watergate Affair, 1972-1974--Sources.
Princeton subject headings:
Executive privilege (Government information)--United States--History--Sources.
National security--United States--History--Sources.
Nixon, Richard M. (Richard Milhous), 1913-1994.
Watergate Affair, 1972-1974--Sources.