The President, Vice President and all civil Officers of the United States, shall be removed from Office on Impeachment for, and Conviction of, Treason, Bribery, or other high Crimes and Misdemeanors. -- https://constitutioncenter.org/interactive-constitution/articles/article-ii
The impeachment and trial of Andrew Johnson, seventeenth president of the United States : a history.
by
David Miller DeWitt,
High Crimes and Misdemeanors
by
Gene Smith
Presidential impeachment; a documentary overview,
by
Presidential impeachment; a documentary overview,

Opening prayers : impeachment trial of the president of the United States, January 7-February 12, 1999
by
Lloyd John Ogilvie
The consequences of perjury and related crimes : hearing before the Committee on the Judiciary, House of Representatives, One Hundred Fifth Congress, second session ... December 1, 1998.
by
United States. Congress. House. Committee on the Judiciary.
Authorization of an inquiry into whether grounds exist for the impeachment of William Jefferson Clinton, President of the United States : meeting of the House Committee on the Judiciary held October 5, 1998 : presentation by inquiry staff, consideration o
by
United States. Congress. House. Committee on the Judiciar
Impeachment Inquiry
by
Government Printing Office Staff
