The city was in ruins and its rebuilding and expansion became a major concern and preoccupation for Bierut during the years that followed. In June 1945, the Provisional Government of National Unity was established in Moscow. In July, Bierut and other Polish leaders participated in the Potsdam Conference, where, together with Stalin, they successfully lobbied for the establishment of Poland's western border at the Oder–Neisse line. The Polish administration in the formerly German lands was to continue until the final delimitation of the frontier in the (future) peace settlement. Poland's newly acquired "Recovered Territories" had thus reached their maximum attainable size. On 30 June 1946, the Polish people's referendum took place. It was done in preparation for the Yalta-mandated national elections; affirmative answers to the three questions given were supposed to demonstrate public support for the issues promoted by the communists. The results were falsified. On 22 September 1946, the KRN passed the electoral rules and in November set the date; the delayed legislative elections were held on 19 January 1947. The PPR-led coalition, running as the Democratic Bloc, was opposed by Mikołajczyk's PSL. The campaign was conducted in an atmosphere of terror and intimidation. Over 80% of the vote was falsely reported to have been cast for the Democratic Bloc and the PSL was practically eliminated as the legal opposition. The newly-elected "Sejm" convened on 4 February 1947 and on the following day it elected Bierut President of the Republic of Poland. The installation ceremony was done in a traditional format and ended with the new president uttering the words "so help me God". On 16 November 1947, during the opening ceremony of the Polish Radio broadcasting station in Wrocław, President Bierut made a speech entitled "For the dissemination of culture". "The artistic and cultural creative process should reflect the great breakthrough that the nation is experiencing. It should, but so far it isn't", he said. Bierut called for greater centralization and planning in culture and art, which, according to him, should form, educate and engross society. The speech was a harbinger of the upcoming norm of socialist realism in Poland. Sometimes, Bierut on his own undertook special interventions with Stalin. He repeatedly and at different times asked Stalin and Lavrentiy Beria about the whereabouts of the missing Polish communists (former members of the disbanded KPP), many of whom were murdered in the Great Purge in the 1930s, but others may have survived.