FILE - This Wednesday, Sept. 4, 1991 file photo shows Soviet President Mikhail Gorbachev talking before the Congress of People's Deputies during a debate on his proposal to transform the Soviet Union into a confederation of sovereign states in Moscow. Former Belarusian leader Stanislav Shushkevich says a historic document that proclaimed the death of the Soviet Union is missing from archives. Officials with Belarus' government and the Russia-dominated alliance of ex-Soviet nations confirmed late Wednesday Feb. 6, 2013, they only have copies.