About this recording 491–6 April 28, 1971 Unknown Conversation No. 491-6 Date: April 28, 1971 Time: Unknown between 12:16 pm and 12:35 pm Location: Oval Office Unknown people [Secret Service Agents] entered. Call to unknown person President's location -Tricia Nixon The unknown persons left at an unknown time before 12:35 pm. Secret White House Tapes | Richard M. Nixon Presidency 491–6 This recording is currently not available on millercenter.org. To listen to it, please email Mike Greco at mdg4u@virginia.edu Previous 488–9 Next 490–1 More Richard M. Nixon Recordings View all Richard M. Nixon tapes 490–1 audio icon 42–106 audio icon 251–18 audio icon 251–19 audio icon 490–2 audio icon 251–20 audio icon 251–21 audio icon 251–22 audio icon 251–23 audio icon 251–24 audio icon