Boeing received $1.3 billion in new orders.

Boeing said three customers have ordered a total of 31 Boeing jetliners. The combined orders are for 10 737-300 jets, 10 737-400s, three 747-300s, seven 757-200s and one 767-200. The orders make the twinjet 737 the best-selling commercial airplane series in history, Boeing said. Beverly Hills-based International Lease Finance Corp. purchased 18 aircraft. Air Europe, the airline subsidiary of Britain’s International Leisure Group, is doubling the size of its Boeing fleet with 12 new jets. And Dallas-based Southwest Airlines has ordered its 40th 737-300.