These are the source references for Episode 2 of Rachel Maddow's Bag Man podcast, which you can listen to here, or through your preferred podcasting service.
Books:
Witcover, Jules. “Very Strange Bedfellows: The Short and Unhappy Marriage of Richard Nixon and Spiro Agnew”, PublicAffairs, 2008
Cohen, Richard and Witcover, Jules. “A Heartbeat Away”, Viking Press, 1974
Agnew, Spiro T. “Go Quietly … Or Else”, William Morrow, 1980
London, Martin. “The Client Decides: A Litigator's Life: Jackie Onassis, Vice President Spiro Agnew, Donald Trump, Roy Cohn, and More”, Eastlake Press, 2017
Coffey, Justin. “Spiro Agnew and The Rise of the Republican Right”, Praeger, 2015
Ehrlichman, John. “Witness to Power: The Nixon Years”, Simon & Schuster Publishing, 1982
Richardson, Elliot. “The Creative Balance: Government, Politics, and The Individual in America’s Third Century.” Holt, Rinehart and Winston. 1976
Articles:
“Agnew Successor In Baltimore Job Indicted In Bribes”, The New York Times (August 24, 1973)
“Texts of Charge Against Vice President and of Grand Jury Criminal Information”, The New York Times (October 11, 1973)
“G.S.A. Says Agnew Office Made Overtures on Pacts”, The New York Times (October 11, 1973)
“Head of the G.S.A. Says Agnew’s Office Recommended Companies For Contracts”, The New York Times, October 11, 1973 (Courtesy of The Weisberg Collection. Hood College. Frederick, MD, USA)
“Nixon Takes Blame As 4 Aides Quit Over Watergate Bugging”, The Atlanta Constitution Newspaper (May 1, 1973)
“Federal Grand Jury Indicts 7 Nixon Aides on Charges of Conspiracy on Watergate; Haldeman Ehrlichman, Mitchell On List”, The New York Times (March 2, 1974)
“Closing In on Agnew: The Prosecutors’ Story” by Aaron Latham. “New York Magazine” (November 26, 1973)
Archival Material:
NBC News Special Report/1973 Presidential Inauguration (January 20, 1973)
NBC Nightly News (August 23, 1973)
NBC News Archives (April 30, 1973)
NBC Nightly News (May 7, 1973)
Spiro T. Agnew 1966 Gubernatorial campaign radio ads (courtesy of the Richard Nixon Presidential Library)
H.R. Haldeman Audio Diaries, March 31, 1970 (Courtesy: Richard Nixon Presidential Library)
NBC Nightly News (June 14, 1973)
NBC News Special Report, Vice President Agnew Speech in Los Angeles (September 29, 1973)
NBC Nightly News (September 19, 1973)