1 – Physicists Ralph Asher Alpher and George Gamow publish the Alpher–Bethe–Gamow paper, about the Big Bang. April 3 United States President Harry S. Truman signs the Marshall Plan, which authorizes $5 billion in aid for 16 countries. Jeju Uprising: Residents revolt on Jeju island, South Korea, eventually leading to the deaths of between 14,000 and 30,000. Beethoven's Symphony No. 9 is played on television in its entirety for the first time, in a series of concerts featuring Arturo Toscanini conducting the NBC Symphony Orchestra in the United States. The chorus is conducted by Robert Shaw. April 5 – 1947–48 Civil War in Mandatory Palestine: Haganah launches Operation Nachshon, provoking the 1948 Palestinian exodus. April 7– The World Health Organization is established by the United Nations. April 9 Jorge Eliécer Gaitán's assassination provokes a violent riot in Bogotá (the Bogotazo), and a further 10 years of violence (La Violencia) across Colombia. The Deir Yassin massacre takes place, in British Mandatory Palestine. April 13 – The Hadassah medical convoy massacre takes place, in British Mandatory Palestine. April 16 – The Organisation for Economic Co-operation and Development is founded, as the Organisation for European Economic Co-operation (OEEC). April 18 – Italian general election, 1948: The first democratic general election with universal suffrage is held in Italy. The Christian Democracy party achieves a majority over the Popular Democratic Front Communist-Socialist coalition. April 19 Burma joins the United Nations. The American Broadcasting Company (otherwise known as ABC) begins television services, on WFIL-TV in Philadelphia (later WPVI-TV). April 22 Civil War in Mandatory Palestine: Battle of Haifa – Jewish paramilitary group Haganah captures Haifa from the Arab Liberation Army. WTVR begins television services. WTVR is the first TV station south of Washington D.C., giving it the nickname "The South's First Television station". April 23 – First National Games of Pakistan held in Karachi. April 24 – The Costa Rican Civil War ends. April 30 The Organization of American States (OAS) is founded. The English-built Land Rover is unveiled at the Amsterdam Motor Show. May May – The RAND Corporation is established, as an independent nonprofit policy research and analysis institution, in the United States. May 9 – Solar eclipse of May 9, 1948: An annular solar eclipse is visible in Japan and South Korea, and is the 32nd solar eclipse of Solar Saros 137. This eclipse is very short, lasting just 0.3 seconds. The path