Three of the major regional travel reservation and services networks, Amadeus Global Travel Distribution, Worldspan and Abacus, announced on Friday that they are interconnecting their computers and are studying other areas of co-operation. Madrid-based Amadeus will link its computer centre in Germany with Worldspan’s system by the first quarter of next year, enabling users of one system to read passenger name records on the other; Amadeus and Singapore-based Abacus, which is already affiliated with Worldspan, will also link systems, and Amadeus and Worldspan are also considering allowing users in one system to change passenger bookings in the other. The agreement could lead on to joint technology development and database management. Amadeus is owned by Air France, Iberia Airlines, and Deutsche Lufthansa AG. Worldspan Global Travel Information Services is owned by Delta Air Lines Inc, NWA Inc’s Northwest Airlines, Trans World Airlines and Abacus Distribution Systems Pte Ltd. And Abacus is owned by All Nippon Airways, Cathay Pacific Airways, China Airlines, Dragonair, Malaysian Airlines, Philippine Airlines, Royal Brunei, Silk Air, Singapore Airlines; Worldspan also has a stake.