Columbia subject headings:
Impeachments--United States.
Johnson, Andrew, 1808-1875--Impeachment.
Harvard subject headings:
Impeachments--United States
Johnson, Andrew, 1808-1875--Impeachment--Trials, litigation, etc.
Johnson, Andrew, 1808-1875--Trials, litigation, etc.
Trials (Impeachment)--United States
Princeton subject headings:
Impeachments--United States.
Johnson, Andrew, 1808-1875--Impeachment.