Before revision: Purpose and origins John and Yoko introduced the idea during a well-received press conference in Vienna on 31 March 1969,"John Lennon & Yoko Ono: Bagism Press Conference 3/31/1969", The Beatles Ultimate Experience.
After revision: Purpose and origins Lennon and Ono introduced the idea during a well-received press conference in Vienna on 31 March 1969,"John Lennon & Yoko Ono: Bagism Press Conference 3/31/1969", The Beatles Ultimate Experience.