31.   A train and infrequent flights between the two cities exist, but visa restrictions make travel difficult.

32.   Aeromexico will begin daily round-trip flights between Ontario and Hermosillo starting in January.

33.   Adleman then ordered the synthesis of DNA molecules corresponding to the cities and to the flight tags representing all the possible flights between one city and another.

34.   Aeroflot, the Russian airline, has been operating flights between Seattle and the Russian Far East and Moscow since earlier this year.

35.   After the move last month, Midway reduced its service to Chicago to a single daily flight between Midway and Raleigh-Durham.

36.   Air France and Continental offer daily nonstop flights between Houston and Paris.

37.   AirTran won the right to offer six daily nonstop flights between Atlanta and La Guardia, a market that Delta now monopolizes.

38.   All flights between the United States and Mexico were canceled.

39.   British Airways allows smoking on flights between London and Eastern Europe, South America, Spain, Russia and Tokyo.

40.   British Airways now also offers regular flights between London and Barbados in the winter.