Uruguay amid accusations of electoral fraud. March 2 The Club of Rome presents the research results leading to its report The Limits to Growth, published later in the month. The Pioneer 10 spacecraft is launched from Cape Kennedy, to be the first man-made spacecraft to leave the solar system. Jean-Bédel Bokassa becomes President of the Central African Republic. March 4 Libya and the Soviet Union sign a cooperation treaty. The Organisation of the Islamic Conference Charter is signed (effective February 28, 1973). March 5 – Greek composer Mikis Theodorakis leaves the Greek Communist Party. March 19 – India and Bangladesh sign the Indo-Bangladeshi Treaty of Friendship, Cooperation and Peace. March 22 The 92nd U.S. Congress votes to send the proposed Equal Rights Amendment to the states for ratification. Eisenstadt v. Baird: The Supreme Court of the U.S. rules that unmarried people have the right to access contraception on the same basis as married couples March 25 – Après toi sung by Vicky Leandros (music by Klaus Munro & Mario Panas, lyric by Klaus Munro & Yves Dessca) wins the Eurovision Song Contest 1972 for Luxembourg. March 26 – An avalanche on Mount Fuji kills 19 climbers. March 27 – The First Sudanese Civil War ends. March 30 – Vietnam War: The Easter Offensive begins after North Vietnamese forces cross into the Demilitarized Zone (DMZ) of South Vietnam April April 10 The U.S. and the Soviet Union join some 70 nations in signing the Biological Weapons Convention, an agreement to ban biological warfare. Tombs containing bamboo slips, among them Sun Tzu's Art of War and Sun Bin's lost military treatise, are accidentally discovered by construction workers in Shandong. The 6.7 Qir earthquake shakes southern Iran with a maximum Mercalli intensity of IX (Violent), killing 5,374 people in the province of Fars. The 44th Annual Academy Awards are held at the Dorothy Chandler Pavilion in Los Angeles. April 13 – The Universal Postal Union decides to recognize the People's Republic of China as the only legitimate Chinese representative, effectively expelling the Republic of China administering Taiwan. April 16 Apollo 16 (John Young, Ken Mattingly, Charlie Duke) is launched. During the mission, the astronauts, driving the Lunar Roving Vehicle, achieve a lunar rover speed record of 18 km/h. Vietnam War – Nguyen Hue Offensive: Prompted by the North Vietnamese offensive, the United States resumes bombing of Hanoi and Haiphong. April 26 – The