About this recording 483–20 Alexander P. Butterfield UNKNOWN April 20, 1971 Alexander P. Butterfield Unknown Secret White House Tapes | Richard M. Nixon Presidency 483–20 Rewind 10 seconds Play/Pause Fast-forward 10 seconds 0:00 Download audio Previous 949–9 Next 450–1 More Richard M. Nixon Recordings View all Richard M. Nixon tapes 450–1 audio icon 47–1 audio icon 450–10 audio icon 450–11 audio icon 450–12 audio icon 450–13 audio icon 450–14 audio icon 450–15 audio icon 450–16 audio icon 450–17 audio icon