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机译:On the existence of small antichains for definable quasi-orders
Univ Vienna, Dept Math, Kolingasse 14-16, A-1090 Vienna, Austria;
Univ Turin, Dipartimento Matemat Giuseppe Peano, Palazzo Campana,Via Carlo Alberto 10, I-10123 Turin, Italy;
Antichain; chain; definable; dichotomy; Dilworth; quasi-order;